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RichardCox

Appropriate Leverage Levels for Forex Trading

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One of the characteristics that separates new traders from experienced traders is the way each uses leverage. One reason for this is that since many starting traders recklessly abuse leverage, they lose their entire trading accounts and are not able to stay in the game long enough to actually become experienced traders. The ones that are able to use leverage responsibly are the ones that are able to construct workable trading plans that can be successfully repeated over time.

 

In fact, you can almost guess how a trader will use leverage based on the amount of money that is in a trading account. Newer traders tend to have smaller amounts of capital when starting and accounts with less than $5,000 tend to approach position sizes in aggressive ways. Since these accounts are much smaller, it becomes very easy for a few trades to go wrong and wipe out the account entirely. Traders with larger account sizes tend to be in less of a rush to make money and the result of that leverage tends to be approached in more conservative ways.

 

Protective Position Sizes

 

Many experienced traders advise newbies to apply leverage ratios of 10:1 or less (which means that at least $1 is deposited for every $10 in a position size). More experienced traders (and those with larger account sizes) tend to have successful trades in larger percentages. While this might seem to be something of a tautology, a large part of how this happens comes with effective uses of leverage that are not overly risky yet still allow for sizable gains.

 

One of the most important trading rules to remember is that excessive leverage levels can quickly magnify losses and leave new traders feeling overly emotional, as though trading is impossible or even that your broker is running a scam operation. These factors can snowball and create a dangerous cycle that can lead new traders discouraged and unwilling to continue.

 

Leverage as Part of Your Strategy

 

Another key point to remember is that recklessly using leverage can even destroy what would otherwise be a solid and successful strategy. So, using leverage effectively can have a significant and direct impact on your overall profits and losses. Since no trading strategy can prepare you for changing market conditions 100% of the time, so it must always be understood that losses can be taken on at any time. The surest way of protecting against these potential changes is to always use stop losses and to keep trading sizes at conservative levels.

 

When constructing your trading strategy it is always a good idea to keep this simple equation in mind, based on the equity in your account:

 

Total Account Equity * Preferred Leverage Ratio = Maximum Trade Position Size (for all open positions combined)

 

So, if you are trading at the upper end of the acceptable leverage range (10:1), an account with $1,000 in total equity will never allow open positions to pass $10,000. Your preferred leverage ratio however, will vary. More conservative traders will be able to use ratios of 2 or 3 to 1, or, perhaps, no leverage at all (a ratio of 1:1). More aggressive traders can still sustain their accounts with slightly higher levels.

 

Of course, leverage can be managed either by adding to your account equity or by decreasing the size of your trades. Most successful traders tend to place their focus on the amount of money that is being put at risk, rather than the potential gains of a trade. Leverage is a powerful tool that can cause one losing trade to completely erase a strong of successful trades. Keeping leverage at conservative levels can help to slow losses when they do occur and can help to protect against losing streaks. Successful traders have confidence in their methods while being sensible in their profit expectations. Successful strategies generally require a sufficient amount of trading capital of sufficient capital (trading accounts worth at least $5,000) and conservative approaches to leverage (with ratios not exceeding 10 to 1).

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It's funny how the most actively traded forex and futures financial products are very highly leveraged. The eurodollar futures contract boasts between 1:1000 - 1:5000 depending on the broker you use and their day trading margin. Non-USA/JPY retail forex brokers typically have anywhere between 1:200 to 1:1000 leverage on offer for most of their currency pairs, and their minimum lot sizes can go down to 10 units of the base currency (although 100 or 1000 units minimum is more common minimum for some accounts).

 

The leverage only is appropriate for determining how many positions per tick or per pip that the account can trade before being unable to trade anymore. This is best done mathematically using a spreadsheet designed for this purpose. This is how you can determine with 100% objectivity how much of an actual pip/tick range in market movement you can handle from initial entry before blowing up your account.

 

One person said it best on a different forum: if you cannot sleep at night with the amount of open positions you have, then you are over-leveraged. It can be a big temptation to overuse leverage, when unaware of the true power of position sizing. One advantage about using the spreadsheet is that you can determine your level of aggression and then copy the lot sizes into your system and forward test different levels to paint a clearer picture of the difference between aggression and recklessness.

 

The idea of not using more that 1:10 leverage is a rehash of the "risk no more than x% per trade" idea. Neither of these abstract-only method address the strategy being used for entries. They also do not address pip or tick value price movement relative to each (or total) position size. Luckily for most traders, price is linear and all these relevant events: pip/tick value, position size, and position value per pip/tick can be calculated precisely from entry to exit (equity stop loss or take profit). Use the spreadsheet or something similar to determine these precise values. It is true that we cannot predict the exact range of price travel all the time. So shouldn't the goal be to focus our attention almost exclusively on the aspects we have control over in the most objective manner possible?

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It's funny how the most actively traded forex and futures financial products are very highly leveraged. The eurodollar futures contract boasts between 1:1000 - 1:5000 depending on the broker you use and their day trading margin. Non-USA/JPY retail forex brokers typically have anywhere between 1:200 to 1:1000 leverage on offer for most of their currency pairs, and their minimum lot sizes can go down to 10 units of the base currency (although 100 or 1000 units minimum is more common minimum for some accounts).

 

The leverage only is appropriate for determining how many positions per tick or per pip that the account can trade before being unable to trade anymore. This is best done mathematically using a spreadsheet designed for this purpose. This is how you can determine with 100% objectivity how much of an actual pip/tick range in market movement you can handle from initial entry before blowing up your account.

 

One person said it best on a different forum: if you cannot sleep at night with the amount of open positions you have, then you are over-leveraged. It can be a big temptation to overuse leverage, when unaware of the true power of position sizing. One advantage about using the spreadsheet is that you can determine your level of aggression and then copy the lot sizes into your system and forward test different levels to paint a clearer picture of the difference between aggression and recklessness.

 

The idea of not using more that 1:10 leverage is a rehash of the "risk no more than x% per trade" idea. Neither of these abstract-only method address the strategy being used for entries. They also do not address pip or tick value price movement relative to each (or total) position size. Luckily for most traders, price is linear and all these relevant events: pip/tick value, position size, and position value per pip/tick can be calculated precisely from entry to exit (equity stop loss or take profit). Use the spreadsheet or something similar to determine these precise values. It is true that we cannot predict the exact range of price travel all the time. So shouldn't the goal be to focus our attention almost exclusively on the aspects we have control over in the most objective manner possible?

 

To further your thinking here a bit if I may... the real issue that should be addressed here is "what am i trading for.... what are my goals". If your goal is to turn $100 into $1 million in 1 year, and you have a hypothetical holy grail strategy that will provide a big enough edge to justify a massive risk amount, then in fact that is what you should be risking per trade, even if it is upwards of 30%.

 

Of course, only fools make it a "goal" to "win the lotto". And if you have such an edge that really could do this...well, you won't need that $100 anyway, you'll get rich almost regardless of any risk management approach.

 

But of coiurse you DON'T have this edge.

 

Now, say your goal is to take a 10K nest egg, and grow it to the point where you can make 50K a year with. And you determine your edge justifies taking a 2% risk per trade, and in doing so it will very likely not suffer more than a 20% drawdown, at any time in th next 10 years, and and with that risk amount you can make about 50% ROI per year... and you want to be able to go full time making that $50K within 7 years.

 

WELLLLLL... now that you actually know what you have, and what you are shooting for, and how long you are willing to give it, and how your method will likely perform over that period of time...

 

you also know what you should risk per trade. And notice how the question or issue of leverage now is actually completely irrelevent.

 

Discussing what leverage one should use on a trade is like discussing what pair of pants you should plan on wearing at your 350th birthday party. It doesn't matter, because your not gonna get to be 350, and even if you were... it has absolutly nothing to do with your goals or why you are trading, or your account, or what your system can handle or anything else.

 

Because when you start talking leverage, as in "how much is enough", you're probably already F'd.

 

I know of no professional trader who even considers leverage as a function of capital. But I know every single one of them looks at risk, reward, drawdown, percent return per year, month, week, expectancy per trade, standardard deviation of drawdown, etc.

 

Why anyone cares about leverage escapes me. It's like caring how much foam rubber they put in your seats in your car, but totally overlooking the miles on the engine, or if the car even drives....etc.

 

Personally 4Ever...I'm wondering who this richard cox guy is... he must have a ghostwriter doing this. his articles are either total fables, or highly irrelevent. I'd be willing to bet anyone $1000 bucks that no one reading this or anything else he's posted tonight will be able to do a single thing with any of it, in terms of trading.

 

Anyway, the leverage issue is age old, and frankly, my trading success or lackthereof is actually more dependent on whether my wife prepared a good dinner for me or not on any particular evening, than it EVER is on my "leverage"

 

TraderX

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I know of no professional trader who even considers leverage as a function of capital. But I know every single one of them looks at risk, reward, drawdown, percent return per year, month, week, expectancy per trade, standardard deviation of drawdown, etc.

 

Why anyone cares about leverage escapes me.

 

I know plenty of traders who do care about both their capital and how much leverage they can get out of it (I think this may just be semantics here ForexTraderX)

 

The first question that should always be asked when someone quotes their returns is - how much leverage are you using as it puts all the others into perspective.

Too often people quote "i made xxxx%" - irrelevant without knowing what that is based on, and those measures you quote help quantify that.

Be wary of those who say - 'I can make you $1mil, I just need access to $10m and for that you only need to put up $200,000"

 

Leverage is a tool to enhance or destroy returns faster or slower depending on the system.

 

To be able to properly measure things historically you need to understand both the capital base and the amount of leverage used.....

 

however in determining how much leverage to actually trade then - the "sleep well" or "heat" measure is probably the best measure their is IMHO.

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I know plenty of traders who do care about both their capital and how much leverage they can get out of it (I think this may just be semantics here ForexTraderX)

 

The first question that should always be asked when someone quotes their returns is - how much leverage are you using as it puts all the others into perspective.

Too often people quote "i made xxxx%" - irrelevant without knowing what that is based on, and those measures you quote help quantify that.

Be wary of those who say - 'I can make you $1mil, I just need access to $10m and for that you only need to put up $200,000"

 

Leverage is a tool to enhance or destroy returns faster or slower depending on the system.

 

To be able to properly measure things historically you need to understand both the capital base and the amount of leverage used.....

 

however in determining how much leverage to actually trade then - the "sleep well" or "heat" measure is probably the best measure their is IMHO.

 

Well... ok, I agree to a degree that it's primarily an argument of semantics.... (lots of those in trading it seems).... however, risk parameters and drawdown statistics cover that as well, and do a better job of it than leverage, IMO.

 

Yes, pro traders do consider leverage in a certain point of view, but on any given trade, it's really risk:reward... and since very few professional traders I know of risk more than 5% of their own equity per trade (heck, most don't even risk 2% per trade), the issue of leverage just doesn't come up, because they are never really "leveraged" more than about 10:1 or 20:1, at MOST.

 

and when it comes to institutional trading, leverage is almost a non-issue, because liquidity becomes the overriding factor... because no on will "leverage" up to the point where liquidity becomes a problem for them... and since they are trading 7, 8, or even 9 figure sums... liquidity becomes an issue long before leverage does.

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and when it comes to institutional trading, leverage is almost a non-issue, because liquidity becomes the overriding factor... because no on will "leverage" up to the point where liquidity becomes a problem for them... and since they are trading 7, 8, or even 9 figure sums... liquidity becomes an issue long before leverage does.

 

I agree that for many traders they may not take into account their leverage, but if you dont understand it then I will gurantee you one thing - your back tested, or historical worst case DD will be broken. Of course depending on what you are trying to achieve is important here, and when introducing institutions into the mix.....well, most are unleveraged, either due to mandates or regulatory or internal risk controls.

but without digressing into the insto world....

 

if a trader tells you he made XXX% or dollars, I would always ask on what leverage - because from that you can guess his other parameters....

which would you rather back

trader A.....2% risk, max historical draw down 30%, returns 50% pa, leverage 2X

trader B.....2% risk, max historical draw down 30%, returns 50% pa, leverage 10X

 

it another measure that many miss use, or neglect or think irrelevant....

Look at what happened when many leveraged themselves up circa 2007......

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I agree that for many traders they may not take into account their leverage, but if you dont understand it then I will gurantee you one thing - your back tested, or historical worst case DD will be broken. Of course depending on what you are trying to achieve is important here, and when introducing institutions into the mix.....well, most are unleveraged, either due to mandates or regulatory or internal risk controls.

but without digressing into the insto world....

 

if a trader tells you he made XXX% or dollars, I would always ask on what leverage - because from that you can guess his other parameters....

which would you rather back

trader A.....2% risk, max historical draw down 30%, returns 50% pa, leverage 2X

trader B.....2% risk, max historical draw down 30%, returns 50% pa, leverage 10X

 

it another measure that many miss use, or neglect or think irrelevant....

Look at what happened when many leveraged themselves up circa 2007......

 

I personally just don't factor in leverage at all.

 

In my trading, I have a fixed stop loss point, and my risk amount is based on a percent loss that will be incurred if i hit that stop loss point.

 

For example, I may have a trade where Ii'm risking 1% of a $10,000 account on a trade with a 100 pip stop.

 

This would be about $1.00 per pip, which is almost not leveraged at all.

 

However, I may have another trade where I'm risking 1% of a $10,000 account on a trade, with a 3 pip stop.

 

That's $33 a pip, and is obviously much more leveraged than the first example. But it doesn't matter, because 1% risk is 1% risk, and $100 potential loss is $100 potential loss.

 

if one demonstrates risk, drawdown, and profits purely in percentage of account equity, then leverage is a mute point. And for my own tradign, as well as most others I know of who trade for a living, a sharpe ratio, or a traders Beta is a far superior data point to determining what type of risk a trader is taking, than "how much is their leverage".

 

maybe it's just a matter of opinion here, or maybe i'm missing something... but I dont' see a single place that leverage amount is important to know that exposure of account equity in terms of % that can be lost or a sharpe ratio, or a beta number, won't give a better insight on.

 

If i'm wrong, please point out where.

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if one demonstrates risk, drawdown, and profits purely in percentage of account equity, then leverage is a mute point. And for my own tradign, as well as most others I know of who trade for a living, a sharpe ratio, or a traders Beta is a far superior data point to determining what type of risk a trader is taking, than "how much is their leverage".

 

maybe it's just a matter of opinion here, or maybe i'm missing something... but I dont' see a single place that leverage amount is important to know that exposure of account equity in terms of % that can be lost or a sharpe ratio, or a beta number, won't give a better insight on.

 

If i'm wrong, please point out where.

 

A: Gaps.

 

Dont worry i am not arguing with you, I am adding an extra measure that when assessing a strategy then leverage is a component.

Otherwise simplistically - why not just say the past draw downs have only been X, therefore we can leverage ourselves to this....plus for all those people who say I return 100% per month - its not generally scalable - hence why leverage is a valid component to understand....it is certainly not a mute point as many have found to their peril in the past.

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A: Gaps.

 

Dont worry i am not arguing with you, I am adding an extra measure that when assessing a strategy then leverage is a component.

Otherwise simplistically - why not just say the past draw downs have only been X, therefore we can leverage ourselves to this....plus for all those people who say I return 100% per month - its not generally scalable - hence why leverage is a valid component to understand....it is certainly not a mute point as many have found to their peril in the past.

 

Ok, i'm 100% with you on this. it is important to understand leverage on a conceptual level, and always consider total exposure (leveraged total exposure) at any given time.

 

Just speaking personally, if I risk even upwards of 2% of my account on a single trade, i never even get into 10:1 leverage... and that's regardless of whether my stop loss is 15 pips, or 100 pips.

 

I think me personallly my average trade works out to be about 5:1 - 8:1 leverage.

 

and for someone who is day trading, I believe risking even 2% per trade is pretty cowboy. Of course, there are mathematical ways of determining what the "appropriate or optimal risk" is for a trade, based on win rate, profit in terms of R, standard deviation of "average losing/winning streaks"...etc.

 

but all that being said, if one is getting just 1 trade per day, and has a 60% win rate, with winners and losers each averaging 1R... risking 2% of ones account per trade will generate approx. 8% per month. If the account is left to grow, within 5 years, a person can take $10,000 and run it up to over 1 million.

 

In another 2.5 years (7.5 years total), that $10K will now be 10 million, and so on...etc.

 

I guess what smacks me funny about the whole idea of needing to know what your leverage is, because you'll likely blow up if you don't understand it...

 

is that if a person has a $10K account, and if they are risking approx. 2% of their account, on a trade in the EUR/USD, and they have a 20 pip stop on the trade....that would leverage them up about 10:1.

 

If they have a 40 pip stop, to acheive the same risk amount on that trade, with the same account size, etc... they would only be leveraged 5:1.

 

And, considering the typical 1-2 pip spread on the EUR/USD for most spot forex traders, if someone has a "strategy" that targets 10 pips or something... they need to overcome a significant disadvantage due to just even a 1 pip spread... making most strategies used by retail traders with retail brokers absent of long term viability if they are going for small pip moves (like, anything less than 10 pips). It's just too much to overcome, due to transaction costs being such a high percentage of your profit on little 10 and 12 pip targets.

 

so, given than it's safe to assume at least a 1 pip spread on the EUR/USD for the retail trader, i would say a minimum "average" target should be about 20 pips. otherwise...the "juice" is just too high for the vast majority over the long run.

 

And now we are basically back where we started. a 20 pip target, with a 10K account, and 2% risk per trade, with a risk:reward ratio of 1:1, and a 60% win rate... you can take 10K over 10 million in about 7 years...and in doing so, you will never exceed 10:1 leverage on any single trade.

 

If this is such a paltry sum for a would be trader, and obviously nothing less than "30% profit per month will do"... then I think that trader has MUCH bigger problems than the potential to over leverage!

 

I do agree with you that it is good to understand how leverage works... and maybe i'm just an arrogant bastard, but I tend to think that if one is blind to the fact that they are greatly over leveraged, and that person has no concept or understanding of why that is bad.... I welcome them to the marketplace, and I only can hope for them to be on the other side of my trades...

 

something akin to driving a Ferrari down a freeway at 160 MPH, and not realizing why that is dangerous.... well, I got a darwin award for ya buddy.

 

ANyway, I think we've beat this horse good and dead. yes, leverage is important to understand, but if one doesn't get that almost intrinsically, instinctively, maybe this isn't the right field for them.

 

FTX

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Bear in mind that most of the brokers do not guarantee Stop Loss and Take profit. Best idea is to take leverage into consideration which leverage you use because the higher the leverage, the higher the risk.

 

Well ok that's true about the brokers, but for me, it's only been an issue maybe 4 or 5 times ever in my trading career, out of thousands of trades... and the WORST I ever had was about 15-20 pips of slippage when the SNB announced they were pegging the euro, and once when the tsunami in japan occured, I think I got about 10 pips of slippage when the news broke.

 

It's just such an incredibly insignificant issue, that if your actually having regular problems with "slippage" causing massive losses because your leverage amount was high, then it's your broker...and if it's not your broker, i'm willing to bet that on your losing trades, your account drops by well over 2% every time you lose.

 

and it's NOT true "the higher the leverage, the higher the risk". and I'll prove it here:

 

A trader has a $10,000 account. He takes a long trade on the EUR/USD with a 10 pip stop, and a 11 pip target (an extra pip to cover his 1 pip spread). He risks 2% of his account balance on this trade, so should the trade hit is stop 10 pips below, he will lose $200 (which is 2% of his 10K)

 

That works out to be about $250,000 USD he "sells" in order to "buy" about $200,000 units of euros (it's a long trade). So, he just leveraged 25:1, and he is risking $200 on this trade should the trade drop 10 pips and get stopped out. That's 2% of his 10K account at risk.

 

Now, say that same trader, on a seperate trade, has another account with 10K in it. He again goes long in the EUR/USD, and he risks $200 on the trade, which is 2% of his account total. HOWEVER, rather than take a 10 pip stop, he takes a 200 pip stop (and a 201 pip target...whatever)

 

In this case, he is risking only $12,560 units (give or take)... so, he is leveraged about 1.25:1. Almost just 1:1... in other words, it's almost no leverage at all.

 

HOWEVER, his risk has NOT decreased at all! he is still risking 2% of his account. he is still risking $200.00.

 

in one example, he is leveraged about 25:1. in the other example, his leverage is barely more than 1:1... yet, his risk has not changed a bit. (unless you count slippage, which as I said earlier, if slippage is an issue, it's not your slippage, it's your broker)

 

So, unless you can show me a way that this math is wrong, or not relevent... then i'm gonna go ahead and say, no, more leverage does NOT necessarily mean more risk.

 

More risk means more risk. More leverage means quite simply a larger or smaller change to amount of investment capital per unit of market price fluctuation.

 

The words are not synonyms of each other.

 

It's like saying "more horsepower in a car makes for a more dangerous car". No. that's simply not true. If you drive the speed limit everywhere, always use your turn signal, never make an illegal lane change, never drive drunk, and always watch the road... well, i dont' care what your horsepower in your car is, you could have 1000 horsepower in your ferrari... your actually about as safe as you ccould be.

 

and your in fact MUCH SAFER than the new teenager with a license who gets drunk for his high school prom and tries to race his buddies to the illegal night club after the dance. That guy could manage to wrap his 130 horsepower toyota around a stop light. But the little old lady obeying every traffic law in her 1K horsepower ferrari? ya, that's simply just never happen to her. she will never wrap her car around a pole, regardless of the horsepower.... ie: leverage.

 

SO in fact, the reality is leverage is related to risk, but in no way directly correlated to risk.

 

Again, if i'm wrong here... please point out where and how. I don't think there is much more to say, but would like to see someone show me where my logic is wrong.

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ForexTraderX

I think your assumptions are correct in many ways - a small account, plenty of liquidity, fixed margins, a stable market.

These are great assumptions that often get thrown out the window in the real world.......and the finance world is scattered with people who forgot these and decided they could amp their returns with extra leverage.

Your logic falls down on the one time it does not work.......eg; you have taken you 10,000 to 10mil - either with a very high win rate or lots of leverage......liquidity becomes an issue.

....and then unless you can only think in % and dont get flustered when a big drawdown occurs when you hit 10m and give back 20%.....etc......

 

I would think the only logic flaw you have is that there is a model v reality and when reality takes over thats all that counts.....eg; you wake up one morning, the brokerage firm you had your account goes belly up, the tax man is asking for his return on last years PL, you get a divorce and you get a margin call......:doh:

 

As I said (not to argue with you) - with enough assumptions there is no logic in the thoughts, but if you choose to ignore (and not saying you dont recognise them) the risks that extra leverage can give you then I think you are being the little old granny in the Ferrari - not using the horsepower, that gets cleaned up by the speeding kid in the 130 hp s...tbox. :)

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ForexTraderX

I think your assumptions are correct in many ways - a small account, plenty of liquidity, fixed margins, a stable market.

These are great assumptions that often get thrown out the window in the real world.......and the finance world is scattered with people who forgot these and decided they could amp their returns with extra leverage.

Your logic falls down on the one time it does not work.......eg; you have taken you 10,000 to 10mil - either with a very high win rate or lots of leverage......liquidity becomes an issue.

....and then unless you can only think in % and dont get flustered when a big drawdown occurs when you hit 10m and give back 20%.....etc......

 

I would think the only logic flaw you have is that there is a model v reality and when reality takes over thats all that counts.....eg; you wake up one morning, the brokerage firm you had your account goes belly up, the tax man is asking for his return on last years PL, you get a divorce and you get a margin call......:doh:

 

As I said (not to argue with you) - with enough assumptions there is no logic in the thoughts, but if you choose to ignore (and not saying you dont recognise them) the risks that extra leverage can give you then I think you are being the little old granny in the Ferrari - not using the horsepower, that gets cleaned up by the speeding kid in the 130 hp s...tbox. :)

 

Siuya, i'll grant you that with more leverage, one does have to be more mindful of potential "black swans"... but having traded through a couple such situations myself (wrong side of the SNB intervention, and in yen when the tsunami and the market whipsawed several hundered pips in a matter of seconds, not to mention a BOJ intervention against me more than once)... I've never experienced slippage anywhere close to as bad as could ever do me any lasting harm.

 

Worst was the SNB, and I lost about 2.5X more on that trade than I had accounted for. which was less than 4% of my account capital.

 

If I really was leveraged big, one can always purchase out of the money options, or what not.

 

mind you, I would approach such a situation differently if I traded equities on a swing basis.... but equities are rarely leveraged much, if at all.

 

If I frequently held forex positions over the weekend, i may be concerened, but I don't do that either.

 

Had I been leveraged in my SNB slipped trade by a factor of 100:1... ya... that would have hurt. it likley woulda wiped out about 25%-30% of my account.

 

but if I was leveraged at 100:1...i'm gambling big on a percentage basis anyway. too big for most traders, and way too big for anyone that plans on staying in the game.

 

I think overall, one has to know that overleveraging is bad. but honestly, other than that single point, i'm not seeing it. we may have to agree on most points, and also agree to disagree on the importance of considering leverage amount when compared to other metrics by which risk and performance can be measured.

 

and as far as big leverage on large dollar sums... it doesn't exist. at taht size of the game, it becomes an issue of capital preservation and incremental, low risk growth. no one is leveraging 10 million up 50 to 1. No one is even leveraging 10 million up at 10:1. And if they are, they are arbing and hedging the snot out of it because that is how the game is played at that level.

 

multiple studies have shown that the larger ones account size is, the less leverage is used...and this is a fairly consistent direct correlation between leverage (or the lack of), and account size.

 

I could go even further as to say that the amount one will make by basically ignoring leverage and just focusing on risk per trade will generate more money a black swan or rare adverse market condition will lose due to that leverage amount...unless of course your risking 10% per trade. which is actually my whole point.

 

Again, it seems that this isn't really important anyway, it may be splitting hairs on such an irrelevent level that it's not even worth continuing the discussion.

 

I mean, if risk was some unknown boogie man in a closet that hides in shadows and couldn't be seen until it was too late...then ya, leverage would really matter.

 

but it's not. stop losses work in all but the most extreme situations, and if your keeping your risk down to 1 or 2% per trade (or less), than those extreme situations could push the market 2, 3 4, or even 5X past your stop. so, you lose maybe 5 or 10% on that situation. Fine.

 

if you were trading with no leverage, but 1 or 2% risk, it would have been a very similar result.

 

At any rate I think this is dead, at least as far as i'm concerened.

 

If there are those who want to pay a great deal of attention to the amount leverage they are or arn't using, that's fine by me.

 

I just stay away from markets that can be highly volatile, such as biotech stocks, and many emerging market equities taht I don't understand. I also don't sell naked options unless I want the underlying at that the strike price anyway.

 

in doing so, i've been able to completely ignore levearge amounts for years now, and it's yet to have any impact on my trading results, black swans or no black swans.

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FWIW -

the last few weeks i have spoken to a couple of people who have recently retired from some of the larger investment banks - (and when i say retired i mean that - they have not been retrenched - they just have enough money to walk away....aged 40-50 yrs) they worked in the trading and derivatives side of their business. They all love the markets, will continue to trade and invest.....

 

All of them talked about various things and the one thing that struck me that they all focused on was the question - how do i get 12-15% on their money without a lot of leverage.

They are happy to use it and know when its appropriate....but their leverage numbers are along the lines of 2 to 4 times, occasionally ten times when well hedged.

 

When I asked them if they are interested in higher leverage with risk controls etc; they all laughed and said even if you get it right a lot its the excessive leverage that will get you in the end.

The other thing they were all very aware of is the key thing is to avoid over trading.

 

Different mindsets of course....but maybe there is something in that for all of us :)

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FWIW -

the last few weeks i have spoken to a couple of people who have recently retired from some of the larger investment banks - (and when i say retired i mean that - they have not been retrenched - they just have enough money to walk away....aged 40-50 yrs) they worked in the trading and derivatives side of their business. They all love the markets, will continue to trade and invest.....

 

All of them talked about various things and the one thing that struck me that they all focused on was the question - how do i get 12-15% on their money without a lot of leverage.

They are happy to use it and know when its appropriate....but their leverage numbers are along the lines of 2 to 4 times, occasionally ten times when well hedged.

 

When I asked them if they are interested in higher leverage with risk controls etc; they all laughed and said even if you get it right a lot its the excessive leverage that will get you in the end.

The other thing they were all very aware of is the key thing is to avoid over trading.

 

Different mindsets of course....but maybe there is something in that for all of us :)

 

- 12-15% per week, month, quarter, year?

- Did these retirees mention the size of the capital they were trading?

 

1:10 leverage with $1-10 mil is probably a different expectation than 1:10 leverage with $1-10k.

 

The institutional mindset on leverage does tend to be much more conservative than the retail side. I suspect the large part is the starting capital. Another part is how retail sales reps advertise vs how institutional traders are recruited.

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I cannot find the link and I do not remember the name now but a well-known blogger and trader has shown with math that leverage above 3x is plain disaster. I think so too. High leverage is a compensation scheme for brokers and market makers to take the money of the newbies.

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- 12-15% per week, month, quarter, year?

- Did these retirees mention the size of the capital they were trading?

 

1:10 leverage with $1-10 mil is probably a different expectation than 1:10 leverage with $1-10k.

 

The institutional mindset on leverage does tend to be much more conservative than the retail side. I suspect the large part is the starting capital. Another part is how retail sales reps advertise vs how institutional traders are recruited.

 

sorry...my bad. per annum.

I sometimes forget the only ones who tend to speak in % other than pa as the default are retail day traders... :)

These guys look to do less trades, and the ones they do have small drawdowns, good upside and are less likely to be day trading....they also generally hedge.

 

You are right about it being a different ball game if you have larger pots of capital....but people should also take note that often these guys have lots of trading experience, seen lots of other traders come and go, they have naturally become more conservative with their own money than with others. (and maybe so should all of us)

.....and given they are institutional and according to many - the smart guys in the room - maybe just maybe its still worth while listening to....but it certainly does not fit the sales reps, or the dreams etc.....

 

as i mentioned....FWIW.

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    • Gold From Wikipedia, the free encyclopedia     Jump to navigation Jump to search This article is about the element. For other uses, see Gold (disambiguation). "Element 79" redirects here. For the anthology, see Element 79 (anthology). Gold, 79Au Gold Appearance metallic yellow Standard atomic weight Ar, std(Au) 196.966570(4)[1] Gold in the periodic table Hydrogen   Helium Lithium Beryllium   Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium   Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium   Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium     Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Ag ↑ Au ↓ Rg platinum ← gold → mercury Atomic number (Z) 79 Group group 11 Period period 6 Block d-block Element category   Transition metal Electron configuration [Xe] 4f14 5d10 6s1 Electrons per shell 2, 8, 18, 32, 18, 1 Physical properties Phase at STP solid Melting point 1337.33 K (1064.18 °C, 1947.52 °F) Boiling point 3243 K (2970 °C, 5378 °F) Density (near r.t.) 19.30 g/cm3 when liquid (at m.p.) 17.31 g/cm3 Heat of fusion 12.55 kJ/mol Heat of vaporization 342 kJ/mol Molar heat capacity 25.418 J/(mol·K) Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1646 1814 2021 2281 2620 3078 Atomic properties Oxidation states −3, −2, −1, 0,[2]+1, +2, +3, +5 (an amphoteric oxide) Electronegativity Pauling scale: 2.54 Ionization energies 1st: 890.1 kJ/mol 2nd: 1980 kJ/mol   Atomic radius empirical: 144 pm Covalent radius 136±6 pm Van der Waals radius 166 pm Spectral lines of gold Other properties Natural occurrence primordial Crystal structure face-centered cubic (fcc) Speed of sound thin rod 2030 m/s (at r.t.) Thermal expansion 14.2 µm/(m·K) (at 25 °C) Thermal conductivity 318 W/(m·K) Electrical resistivity 22.14 nΩ·m (at 20 °C) Magnetic ordering diamagnetic[3] Magnetic susceptibility −28.0·10−6 cm3/mol (at 296 K)[4] Tensile strength 120 MPa Young's modulus 79 GPa Shear modulus 27 GPa Bulk modulus 180 GPa[5] Poisson ratio 0.4 Mohs hardness 2.5 Vickers hardness 188–216 MPa Brinell hardness 188–245 MPa CAS Number 7440-57-5 History Naming from Latin aurum, meaning gold Discovery In the Middle East (before 6000 BCE) Main isotopes of gold Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct 195Au syn 186.10 d ε 195Pt 196Au syn 6.183 d ε 196Pt β− 196Hg 197Au 100% stable 198Au syn 2.69517 d β− 198Hg 199Au syn 3.169 d β− 199Hg view talk edit | references Gold is a chemical element with the symbol Au (from Latin: aurum) and atomic number 79, making it one of the higher atomic number elements that occur naturally. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native) form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the native element silver (as electrum) and also naturally alloyed with copper and palladium. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of nitric acid and hydrochloric acid, which forms a soluble tetrachloroaurate anion. Gold is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to refine gold and to confirm the presence of gold in metallic objects, giving rise to the term acid test. Gold also dissolves in alkaline solutions of cyanide, which are used in mining and electroplating. Gold dissolves in mercury, forming amalgam alloys, but this is not a chemical reaction. A relatively rare element,[6][7] gold is a precious metal that has been used for coinage, jewelry, and other arts throughout recorded history. In the past, a gold standard was often implemented as a monetary policy, but gold coins ceased to be minted as a circulating currency in the 1930s, and the world gold standard was abandoned for a fiat currency system after 1971. A total of 186,700 tonnes of gold exists above ground, as of 2015.[8] The world consumption of new gold produced is about 50% in jewelry, 40% in investments, and 10% in industry.[9] Gold's high malleability, ductility, resistance to corrosion and most other chemical reactions, and conductivity of electricity have led to its continued use in corrosion resistant electrical connectors in all types of computerized devices (its chief industrial use). Gold is also used in infrared shielding, colored-glass production, gold leafing, and tooth restoration. Certain gold salts are still used as anti-inflammatories in medicine. As of 2017, the world's largest gold producer by far was China with 440 tonnes per year.[10] Contents 1 Characteristics 1.1 Color 1.2 Isotopes 1.2.1 Synthesis 2 Chemistry 2.1 Rare oxidation states 2.2 Medicinal uses 3 Origin 3.1 Gold production in the Universe 3.2 Asteroid origin theories 3.3 Mantle return theories 4 Occurrence 4.1 Seawater 5 History 5.1 Etymology 5.2 Culture 6 Production 6.1 Mining and prospecting 6.2 Extraction and refining 6.3 Consumption 6.4 Pollution 7 Monetary use 7.1 Price 7.2 History 8 Other applications 8.1 Jewelry 8.2 Electronics 8.3 Medicine 8.4 Cuisine 8.5 Miscellanea 9 Toxicity 10 See also 11 References 12 External links Characteristics   Gold can be drawn into a monoatomic wire, and then stretched more before it breaks.   A gold nugget of 0.5 cm (0.20 in) in size can be hammered into a gold foil of about 0.5 m2 (5.4 sq ft) area. Gold is the most malleable of all metals. It can be drawn into a monoatomic wire, and then stretched about twice before it breaks.[citation needed] Such nanowires distort via formation, reorientation and migration of dislocations and crystal twins without noticeable hardening.[11] A single gram of gold can be beaten into a sheet of 1 square meter, and an avoirdupois ounce into 300 square feet. Gold leaf can be beaten thin enough to become semi-transparent. The transmitted light appears greenish blue, because gold strongly reflects yellow and red.[12] Such semi-transparent sheets also strongly reflect infrared light, making them useful as infrared (radiant heat) shields in visors of heat-resistant suits, and in sun-visors for spacesuits.[13] Gold is a good conductor of heat and electricity. Gold has a density of 19.3 g/cm3, almost identical to that of tungsten at 19.25 g/cm3; as such, tungsten has been used in counterfeiting of gold bars, such as by plating a tungsten bar with gold,[14][15][16][17] or taking an existing gold bar, drilling holes, and replacing the removed gold with tungsten rods.[18] By comparison, the density of lead is 11.34 g/cm3, and that of the densest element, osmium, is 22.588±0.015 g/cm3.[19] Color Main article: Colored gold   Different colors of Ag–Au–Cu alloys Whereas most metals are gray or silvery white, gold is slightly reddish-yellow.[20] This color is determined by the frequency of plasma oscillations among the metal's valence electrons, in the ultraviolet range for most metals but in the visible range for gold due to relativistic effects affecting the orbitals around gold atoms.[21][22] Similar effects impart a golden hue to metallic caesium. Common colored gold alloys include the distinctive eighteen-karat rose gold created by the addition of copper. Alloys containing palladium or nickel are also important in commercial jewelry as these produce white gold alloys. Fourteen-karat gold-copper alloy is nearly identical in color to certain bronze alloys, and both may be used to produce police and other badges. Fourteen- and eighteen-karat gold alloys with silver alone appear greenish-yellow and are referred to as green gold. Blue gold can be made by alloying with iron, and purple gold can be made by alloying with aluminium. Less commonly, addition of manganese, indium, and other elements can produce more unusual colors of gold for various applications.[23] Colloidal gold, used by electron-microscopists, is red if the particles are small; larger particles of colloidal gold are blue.[24] Isotopes Main article: Isotopes of gold Gold has only one stable isotope, 197 Au, which is also its only naturally occurring isotope, so gold is both a mononuclidic and monoisotopic element. Thirty-six radioisotopes have been synthesized, ranging in atomic mass from 169 to 205. The most stable of these is 195 Au with a half-life of 186.1 days. The least stable is 171 Au, which decays by proton emission with a half-life of 30 µs. Most of gold's radioisotopes with atomic masses below 197 decay by some combination of proton emission, α decay, and β+ decay. The exceptions are 195 Au, which decays by electron capture, and 196 Au, which decays most often by electron capture (93%) with a minor β− decay path (7%).[25] All of gold's radioisotopes with atomic masses above 197 decay by β− decay.[26] At least 32 nuclear isomers have also been characterized, ranging in atomic mass from 170 to 200. Within that range, only 178 Au, 180 Au, 181 Au, 182 Au, and 188 Au do not have isomers. Gold's most stable isomer is 198m2 Au with a half-life of 2.27 days. Gold's least stable isomer is 177m2 Au with a half-life of only 7 ns. 184m1 Au has three decay paths: β+ decay, isomeric transition, and alpha decay. No other isomer or isotope of gold has three decay paths.[26] Synthesis The production of gold from a more common element, such as lead, has long been a subject of human inquiry, and the ancient and medieval discipline of alchemy often focused on it; however, the transmutation of the chemical elements did not become possible until the understanding of nuclear physics in the 20th century. The first synthesis of gold was conducted by Japanese physicist Hantaro Nagaoka, who synthesized gold from mercury in 1924 by neutron bombardment.[27] An American team, working without knowledge of Nagaoka's prior study, conducted the same experiment in 1941, achieving the same result and showing that the isotopes of gold produced by it were all radioactive.[28] Gold can currently be manufactured in a nuclear reactor by irradiation either of platinum or mercury. Only the mercury isotope 196Hg, which occurs with a frequency of 0.15% in natural mercury, can be converted to gold by neutron capture, and following electron capture-decay into 197Au with slow neutrons. Other mercury isotopes are converted when irradiated with slow neutrons into one another, or formed mercury isotopes which beta decay into thallium. Using fast neutrons, the mercury isotope 198Hg, which composes 9.97% of natural mercury, can be converted by splitting off a neutron and becoming 197Hg, which then disintegrates to stable gold. This reaction, however, possesses a smaller activation cross-section and is feasible only with un-moderated reactors. It is also possible to eject several neutrons with very high energy into the other mercury isotopes in order to form 197Hg. However, such high-energy neutrons can be produced only by particle accelerators.[clarification needed]   Chemistry   Gold(III) chloride solution in water Although gold is the most noble of the noble metals,[29][30] it still forms many diverse compounds. The oxidation state of gold in its compounds ranges from −1 to +5, but Au(I) and Au(III) dominate its chemistry. Au(I), referred to as the aurous ion, is the most common oxidation state with soft ligands such as thioethers, thiolates, and tertiary phosphines. Au(I) compounds are typically linear. A good example is Au(CN)2−, which is the soluble form of gold encountered in mining. The binary gold halides, such as AuCl, form zigzag polymeric chains, again featuring linear coordination at Au. Most drugs based on gold are Au(I) derivatives.[31] Au(III) (referred to as the auric) is a common oxidation state, and is illustrated by gold(III) chloride, Au2Cl6. The gold atom centers in Au(III) complexes, like other d8 compounds, are typically square planar, with chemical bonds that have both covalent and ionic character. Gold does not react with oxygen at any temperature[32] and, up to 100 °C, is resistant to attack from ozone.[33] Some free halogens react with gold.[34] Gold is strongly attacked by fluorine at dull-red heat[35] to form gold(III) fluoride. Powdered gold reacts with chlorine at 180 °C to form AuCl3.[36] Gold reacts with bromine at 140 °C to form gold(III) bromide, but reacts only very slowly with iodine to form the monoiodide. Gold does not react with sulfur directly,[37] but gold(III) sulfide can be made by passing hydrogen sulfide through a dilute solution of gold(III) chloride or chlorauric acid. Gold readily dissolves in mercury at room temperature to form an amalgam, and forms alloys with many other metals at higher temperatures. These alloys can be produced to modify the hardness and other metallurgical properties, to control melting point or to create exotic colors.[23] Gold is unaffected by most acids. It does not react with hydrofluoric, hydrochloric, hydrobromic, hydriodic, sulfuric, or nitric acid. It does react with selenic acid, and is dissolved by aqua regia, a 1:3 mixture of nitric acid and hydrochloric acid. Nitric acid oxidizes the metal to +3 ions, but only in minute amounts, typically undetectable in the pure acid because of the chemical equilibrium of the reaction. However, the ions are removed from the equilibrium by hydrochloric acid, forming AuCl4− ions, or chloroauric acid, thereby enabling further oxidation. Gold is similarly unaffected by most bases. It does not react with aqueous, solid, or molten sodium or potassium hydroxide. It does however, react with sodium or potassium cyanide under alkaline conditions when oxygen is present to form soluble complexes.[37] Common oxidation states of gold include +1 (gold(I) or aurous compounds) and +3 (gold(III) or auric compounds). Gold ions in solution are readily reduced and precipitated as metal by adding any other metal as the reducing agent. The added metal is oxidized and dissolves, allowing the gold to be displaced from solution and be recovered as a solid precipitate. Rare oxidation states Less common oxidation states of gold include −1, +2, and +5. The −1 oxidation state occurs in aurides, compounds containing the Au−anion. Caesium auride (CsAu), for example, crystallizes in the caesium chloride motif;[38] rubidium, potassium, and tetramethylammonium aurides are also known.[39] Gold has the highest electron affinity of any metal, at 222.8 kJ/mol, making Au− a stable species.[40] Gold(II) compounds are usually diamagnetic with Au–Au bonds such as [Au(CH2)2P(C6H5)2]2Cl2. The evaporation of a solution of Au(OH) 3 in concentrated H 2SO 4 produces red crystals of gold(II) sulfate, Au2(SO4)2. Originally thought to be a mixed-valence compound, it has been shown to contain Au4+ 2 cations, analogous to the better-known mercury(I) ion, Hg2+ 2 .[41][42] A gold(II) complex, the tetraxenonogold(II) cation, which contains xenon as a ligand, occurs in [AuXe4](Sb2F11)2.[43] Gold pentafluoride, along with its derivative anion, AuF− 6, and its difluorine complex, gold heptafluoride, is the sole example of gold(V), the highest verified oxidation state.[44] Some gold compounds exhibit aurophilic bonding, which describes the tendency of gold ions to interact at distances that are too long to be a conventional Au–Au bond but shorter than van der Waals bonding. The interaction is estimated to be comparable in strength to that of a hydrogen bond. Well-defined cluster compounds are numerous.[39] In such cases, gold has a fractional oxidation state. A representative example is the octahedral species {Au(P(C6H5)3)}62+. Gold chalcogenides, such as gold sulfide, feature equal amounts of Au(I) and Au(III). Medicinal uses Medicinal applications of gold and its complexes have a long history dating back thousands of years.[45] Several gold complexes have been applied to treat rheumatoid arthritis, the most frequently used being aurothiomalate, aurothioglucose, and auranofin. Both gold(I) and gold(III) compounds have been investigated as possible anti-cancer drugs. For gold(III) complexes, reduction to gold(0/I) under physiological conditions has to be considered. Stable complexes can be generated using different types of bi-, tri-, and tetradentate ligand systems, and their efficacy has been demonstrated in vitro and in vivo.[46] Origin Gold production in the Universe   Schematic of a NE (left) to SW (right) cross-section through the 2.020 billion year old Vredefort impact crater in South Africa and how it distorted the contemporary geological structures. The present erosion level is shown. Johannesburg is located where the Witwatersrand Basin (the yellow layer) is exposed at the "present surface" line, just inside the crater rim, on the left. Not to scale. Gold is thought to have been produced in supernova nucleosynthesis, and from the collision of neutron stars,[47] and to have been present in the dust from which the Solar System formed.[48] Traditionally, gold in the universe is thought to have formed by the r-process (rapid neutron capture) in supernova nucleosynthesis,[49] but more recently it has been suggested that gold and other elements heavier than iron may also be produced in quantity by the r-process in the collision of neutron stars.[50] In both cases, satellite spectrometers at first only indirectly detected the resulting gold.[51] However, in August 2017, the spectrascopic signatures of heavy elements, including gold, were observed by electromagnetic observatories in the GW170817 neutron star merger event, after gravitational wave detectors confirmed the event as a neutron star merger.[52] Current astrophysical models suggest that this single neutron star merger event generated between 3 and 13 Earth masses of gold. This amount, along with estimations of the rate of occurrence of these neutron start merger events, suggests that such mergers may produce enough gold to account for most of the abundance of this element in the universe.[53] Asteroid origin theories Because the Earth was molten when it was formed, almost all of the gold present in the early Earth probably sank into the planetary core. Therefore, most of the gold that is in the Earth's crust and mantle has in one model thought to have been delivered to Earth later, by asteroid impacts during the Late Heavy Bombardment, about 4 billion years ago.[54][55] Gold which is reachable by humans has, in one case, been associated with a particular asteroid impact. The asteroid that formed Vredefort crater 2.020 billion years ago is often credited with seeding the Witwatersrand basin in South Africa with the richest gold deposits on earth.[56][57][58][59] However, this scenario is now questioned. The gold-bearing Witwatersrand rocks were laid down between 700 and 950 million years before the Vredefort impact.[60][61] These gold-bearing rocks had furthermore been covered by a thick layer of Ventersdorp lavas and the Transvaal Supergroup of rocks before the meteor struck, and thus the gold did not actually arrive in the asteroid/meteorite. What the Vredefort impact achieved, however, was to distort the Witwatersrand basin in such a way that the gold-bearing rocks were brought to the present erosion surface in Johannesburg, on the Witwatersrand, just inside the rim of the original 300 km diameter crater caused by the meteor strike. The discovery of the deposit in 1886 launched the Witwatersrand Gold Rush. Some 22% of all the gold that is ascertained to exist today on Earth has been extracted from these Witwatersrand rocks.[61] Mantle return theories Notwithstanding the impact above, much of the rest of the gold on Earth is thought to have been incorporated into the planet since its very beginning, as planetesimals formed the planet's mantle, early in Earth's creation. In 2017, an international group of scientists, established that gold "came to the Earth's surface from the deepest regions of our planet",[62] the mantle, evidenced by their findings at Deseado Massif in the Argentinian Patagonia.[63][clarification needed] Occurrence On Earth, gold is found in ores in rock formed from the Precambrian time onward.[64] It most often occurs as a native metal, typically in a metal solid solution with silver (i.e. as a gold silver alloy). Such alloys usually have a silver content of 8–10%. Electrum is elemental gold with more than 20% silver. Electrum's color runs from golden-silvery to silvery, dependent upon the silver content. The more silver, the lower the specific gravity. Native gold occurs as very small to microscopic particles embedded in rock, often together with quartz or sulfide minerals such as "Fool's Gold", which is a pyrite.[65] These are called lode deposits. The metal in a native state is also found in the form of free flakes, grains or larger nuggets[64] that have been eroded from rocks and end up in alluvial deposits called placer deposits. Such free gold is always richer at the surface of gold-bearing veins[clarification needed] owing to the oxidation of accompanying minerals followed by weathering, and washing of the dust into streams and rivers, where it collects and can be welded by water action to form nuggets. Gold sometimes occurs combined with tellurium as the minerals calaverite, krennerite, nagyagite, petzite and sylvanite (see telluride minerals), and as the rare bismuthide maldonite (Au2Bi) and antimonide aurostibite (AuSb2). Gold also occurs in rare alloys with copper, lead, and mercury: the minerals auricupride (Cu3Au), novodneprite (AuPb3) and weishanite ((Au, Ag)3Hg2). Recent research suggests that microbes can sometimes play an important role in forming gold deposits, transporting and precipitating gold to form grains and nuggets that collect in alluvial deposits.[66] Another recent study has claimed water in faults vaporizes during an earthquake, depositing gold. When an earthquake strikes, it moves along a fault. Water often lubricates faults, filling in fractures and jogs. About 6 miles (10 kilometers) below the surface, under incredible temperatures and pressures, the water carries high concentrations of carbon dioxide, silica, and gold. During an earthquake, the fault jog suddenly opens wider. The water inside the void instantly vaporizes, flashing to steam and forcing silica, which forms the mineral quartz, and gold out of the fluids and onto nearby surfaces.[67] Seawater The world's oceans contain gold. Measured concentrations of gold in the Atlantic and Northeast Pacific are 50–150 femtomol/L or 10–30 parts per quadrillion (about 10–30 g/km3). In general, gold concentrations for south Atlantic and central Pacific samples are the same (~50 femtomol/L) but less certain. Mediterranean deep waters contain slightly higher concentrations of gold (100–150 femtomol/L) attributed to wind-blown dust and/or rivers. At 10 parts per quadrillion the Earth's oceans would hold 15,000 tonnes of gold.[68] These figures are three orders of magnitude less than reported in the literature prior to 1988, indicating contamination problems with the earlier data. A number of people have claimed to be able to economically recover gold from sea water, but they were either mistaken or acted in an intentional deception. Prescott Jernegan ran a gold-from-seawater swindle in the United States in the 1890s, as did an English fraudster in the early 1900s.[69]Fritz Haber did research on the extraction of gold from sea water in an effort to help pay Germany's reparations following World War I.[70] Based on the published values of 2 to 64 ppb of gold in seawater a commercially successful extraction seemed possible. After analysis of 4,000 water samples yielding an average of 0.004 ppb it became clear that extraction would not be possible and he stopped the project.[71] History   An Indian tribute-bearer at Apadana, from the Achaemenid satrapy of Hindush, carrying gold on a yoke, circa 500 BC.[72]   Muisca raft, between circa 600-1600 AD. The figure refers to the ceremony of the legend of El Dorado. The zipa used to cover his body in gold dust, and from his raft, he offered treasures to the Guatavita goddess in the middle of the sacred lake. This old Muisca tradition became the origin of the legend of El Dorado. This Muisca raft figure is on display in the Gold Museum, Bogotá, Colombia. The earliest recorded metal employed by humans appears to be gold, which can be found free or "native". Small amounts of natural gold have been found in Spanish caves used during the late Paleolithic period, c. 40,000 BC.[73] Gold artifacts made their first appearance at the very beginning of the pre-dynastic period in Egypt, at the end of the fifth millennium BC and the start of the fourth, and smelting was developed during the course of the 4th millennium; gold artifacts appear in the archeology of Lower Mesopotamia during the early 4th millennium.[74] Gold artifacts in the Balkans appear from the 4th millennium BC, such as those found in the Varna Necropolis near Lake Varna in Bulgaria, thought by one source (La Niece 2009) to be the earliest "well-dated" find of gold artifacts.[64] As of 1990, gold artifacts found at the Nahal Qana cave cemetery of the 4th millennium BC in West Bank (Occupied PAlestinian Territories) were the earliest from the Levant.[75] Gold artifacts such as the golden hats and the Nebra disk appeared in Central Europe from the 2nd millennium BC Bronze Age. The oldest known map of a gold mine was drawn in the 19th Dynasty of Ancient Egypt (1320–1200 BC), whereas the first written reference to gold was recorded in the 12th Dynasty around 1900 BC.[76]Egyptian hieroglyphs from as early as 2600 BC describe gold, which King Tushratta of the Mitanni claimed was "more plentiful than dirt" in Egypt.[77] Egypt and especially Nubia had the resources to make them major gold-producing areas for much of history. One of the earliest known maps, known as the Turin Papyrus Map, shows the plan of a gold mine in Nubia together with indications of the local geology. The primitive working methods are described by both Strabo and Diodorus Siculus, and included fire-setting. Large mines were also present across the Red Sea in what is now Saudi Arabia.   Ancient golden Kritonios Crown, funerary or marriage material, 370–360 BC. From a grave in Armento, Campania Gold is mentioned in the Amarna letters numbered 19[78] and 26[79] from around the 14th century BC.[80][81] Gold is mentioned frequently in the Old Testament, starting with Genesis 2:11 (at Havilah), the story of the golden calf, and many parts of the temple including the Menorah and the golden altar. In the New Testament, it is included with the gifts of the magi in the first chapters of Matthew. The Book of Revelation 21:21 describes the city of New Jerusalem as having streets "made of pure gold, clear as crystal". Exploitation of gold in the south-east corner of the Black Sea is said to date from the time of Midas, and this gold was important in the establishment of what is probably the world's earliest coinage in Lydia around 610 BC.[82] The legend of the golden fleece dating from eighth century BCE may refer to the use of fleeces to trap gold dust from placer deposits in the ancient world. From the 6th or 5th century BC, the Chu (state) circulated the Ying Yuan, one kind of square gold coin. In Roman metallurgy, new methods for extracting gold on a large scale were developed by introducing hydraulic mining methods, especially in Hispania from 25 BC onwards and in Dacia from 106 AD onwards. One of their largest mines was at Las Medulas in León, where seven long aqueducts enabled them to sluice most of a large alluvial deposit. The mines at Roşia Montană in Transylvania were also very large, and until very recently, still mined by opencast methods. They also exploited smaller deposits in Britain, such as placer and hard-rock deposits at Dolaucothi. The various methods they used are well described by Pliny the Elder in his encyclopedia Naturalis Historia written towards the end of the first century AD. During Mansa Musa's (ruler of the Mali Empire from 1312 to 1337) hajj to Mecca in 1324, he passed through Cairo in July 1324, and was reportedly accompanied by a camel train that included thousands of people and nearly a hundred camels where he gave away so much gold that it depressed the price in Egypt for over a decade, causing high inflation.[83] A contemporary Arab historian remarked:   Gold coin of Eucratides I (171–145 BC), one of the Hellenistic rulers of ancient Ai-Khanoum. This is the largest known gold coin minted in antiquity (169,20 g; 58 mm).[85] The European exploration of the Americas was fueled in no small part by reports of the gold ornaments displayed in great profusion by Native American peoples, especially in Mesoamerica, Peru, Ecuador and Colombia. The Aztecs regarded gold as the product of the gods, calling it literally "god excrement" (teocuitlatl in Nahuatl), and after Moctezuma II was killed, most of this gold was shipped to Spain.[86] However, for the indigenous peoples of North America gold was considered useless and they saw much greater value in other minerals which were directly related to their utility, such as obsidian, flint, and slate.[87]El Dorado is applied to a legendary story in which precious stones were found in fabulous abundance along with gold coins. The concept of El Dorado underwent several transformations, and eventually accounts of the previous myth were also combined with those of a legendary lost city. El Dorado, was the term used by the Spanish Empire to describe a mythical tribal chief (zipa) of the Muisca native people in Colombia, who, as an initiation rite, covered himself with gold dust and submerged in Lake Guatavita. The legends surrounding El Dorado changed over time, as it went from being a man, to a city, to a kingdom, and then finally to an empire. Gold played a role in western culture, as a cause for desire and of corruption, as told in children's fables such as Rumpelstiltskin—where Rumpelstiltskin turns hay into gold for the peasant's daughter in return for her child when she becomes a princess—and the stealing of the hen that lays golden eggs in Jack and the Beanstalk. The top prize at the Olympic Games and many other sports competitions is the gold medal. 75% of the presently accounted for gold has been extracted since 1910. It has been estimated that the currently known amount of gold internationally would form a single cube 20 m (66 ft) on a side (equivalent to 8,000 m3).[88] One main goal of the alchemists was to produce gold from other substances, such as lead — presumably by the interaction with a mythical substance called the philosopher's stone. Although they never succeeded in this attempt, the alchemists did promote an interest in systematically finding out what can be done with substances, and this laid the foundation for today's chemistry. Their symbol for gold was the circle with a point at its center (☉), which was also the astrological symbol and the ancient Chinese character for the Sun. The Dome of the Rock is covered with an ultra-thin golden glassier. The Sikh Golden temple, the Harmandir Sahib, is a building covered with gold. Similarly the Wat Phra Kaew emerald Buddhist temple (wat) in Thailand has ornamental gold-leafed statues and roofs. Some European king and queen's crowns were made of gold, and gold was used for the bridal crown since antiquity. An ancient Talmudic text circa 100 AD describes Rachel, wife of Rabbi Akiva, receiving a "Jerusalem of Gold" (diadem). A Greek burial crown made of gold was found in a grave circa 370 BC. Etymology   An early mention of gold in the Beowulf "Gold" is cognate with similar words in many Germanic languages, deriving via Proto-Germanic *gulþą from Proto-Indo-European *ǵʰelh₃- ("to shine, to gleam; to be yellow or green").[89][90] The symbol Au is from the Latin: aurum, the Latin word for "gold".[91] The Proto-Indo-European ancestor of aurum was *h₂é-h₂us-o-, meaning "glow". This word is derived from the same root (Proto-Indo-European *h₂u̯es- "to dawn") as *h₂éu̯sōs, the ancestor of the Latin word Aurora, "dawn".[92] This etymological relationship is presumably behind the frequent claim in scientific publications that aurum meant "shining dawn".[93] Culture This section needs additional citations for verification. (February 2014) (Learn how and when to remove this template message) Outside chemistry, gold is mentioned in a variety of expressions, most often associated with intrinsic worth.[40] Great human achievements are frequently rewarded with gold, in the form of gold medals, gold trophies and other decorations. Winners of athletic events and other graded competitions are usually awarded a gold medal. Many awards such as the Nobel Prize are made from gold as well. Other award statues and prizes are depicted in gold or are gold plated (such as the Academy Awards, the Golden Globe Awards, the Emmy Awards, the Palme d'Or, and the British Academy Film Awards). Aristotle in his ethics used gold symbolism when referring to what is now known as the golden mean. Similarly, gold is associated with perfect or divine principles, such as in the case of the golden ratio and the golden rule. Gold is further associated with the wisdom of aging and fruition. The fiftieth wedding anniversary is golden. A person's most valued or most successful latter years are sometimes considered "golden years". The height of a civilization is referred to as a golden age. In some forms of Christianity and Judaism, gold has been associated both with holiness and evil. In the Book of Exodus, the Golden Calf is a symbol of idolatry, while in the Book of Genesis, Abraham was said to be rich in gold and silver, and Moses was instructed to cover the Mercy Seat of the Ark of the Covenant with pure gold. In Byzantine iconography the halos of Christ, Mary and the Christian saints are often golden. According to Christopher Columbus, those who had something of gold were in possession of something of great value on Earth and a substance to even help souls to paradise.[94] Wedding rings are typically made of gold. It is long lasting and unaffected by the passage of time and may aid in the ring symbolism of eternal vows before God and the perfection the marriage signifies. In Orthodox Christian wedding ceremonies, the wedded couple is adorned with a golden crown (though some opt for wreaths, instead) during the ceremony, an amalgamation of symbolic rites. Production Main article: List of countries by gold production   Time trend of gold production The World Gold Council states that as of the end of 2017, "there were 187,200 tonnes of stocks in existence above ground". This can be represented by a cube with an edge length of about 21 meters.[95] At $1,349 per troy ounce, 187,200 metric tonnes of gold would have a value of $8.9 trillion. According to the United States Geological Survey in 2016, about 5,726,000,000 troy ounces (178,100 t) of gold has been produced since the beginning of civilization, of which 85% remains in use.[96] In 2017, the world's largest gold producer by far was China with 440 tonnes. The second-largest producer, Australia, mined 300 tonnes in the same year, followed by Russia with 255 tonnes.[10] Mining and prospecting Main articles: Gold mining and Gold prospecting   A miner underground at Pumsaint gold mine, Wales; c. 1938. Since the 1880s, South Africa has been the source of a large proportion of the world's gold supply, and about 22% of the gold presently accounted is from South Africa. Production in 1970 accounted for 79% of the world supply, about 1,480 tonnes. In 2007 China (with 276 tonnes) overtook South Africa as the world's largest gold producer, the first time since 1905 that South Africa has not been the largest.[97] As of 2017, China was the world's leading gold-mining country, followed in order by Australia, Russia, the United States, Canada, and Peru. South Africa, which had dominated world gold production for most of the 20th century, had declined to sixth place.[10] Other major producers are the Ghana, Burkina Faso, Mali, Indonesia and Uzbekistan.   Relative sizes of an 860 kg block of gold ore and the 30 g of gold that can be extracted from it, Toi gold mine, Japan. In South America, the controversial project Pascua Lama aims at exploitation of rich fields in the high mountains of Atacama Desert, at the border between Chile and Argentina. Today about one-quarter of the world gold output is estimated to originate from artisanal or small scale mining.[98] The city of Johannesburg located in South Africa was founded as a result of the Witwatersrand Gold Rush which resulted in the discovery of some of the largest natural gold deposits in recorded history. The gold fields are confined to the northern and north-western edges of the Witwatersrand basin, which is a 5–7 km thick layer of archean rocks located, in most places, deep under the Free State, Gauteng and surrounding provinces.[99] These Witwatersrand rocks are exposed at the surface on the Witwatersrand, in and around Johannesburg, but also in isolated patches to the south-east and south-west of Johannesburg, as well as in an arc around the Vredefort Dome which lies close to the center of the Witwatersrand basin.[60][99] From these surface exposures the basin dips extensively, requiring some of the mining to occur at depths of nearly 4000 m, making them, especially the Savuka and TauTona mines to the south-west of Johannesburg, the deepest mines on earth. The gold is found only in six areas where archean rivers from the north and north-west formed extensive pebbly Braided river deltas before draining into the "Witwatersrand sea" where the rest of the Witwatersrand sediments were deposited.[99] The Second Boer War of 1899–1901 between the British Empire and the Afrikaner Boers was at least partly over the rights of miners and possession of the gold wealth in South Africa. During the 19th century, gold rushes occurred whenever large gold deposits were discovered. The first documented discovery of gold in the United States was at the Reed Gold Mine near Georgeville, North Carolina in 1803.[100] The first major gold strike in the United States occurred in a small north Georgia town called Dahlonega.[101] Further gold rushes occurred in California, Colorado, the Black Hills, Otago in New Zealand, Australia, Witwatersrand in South Africa, and the Klondike in Canada. Extraction and refining Main article: Gold extraction Gold jewelry consumption by country in tonnes[102][103][104] Country 2009 2010 2011 2012 2013  India 442.37 745.70 986.3 864 974  China 376.96 428.00 921.5 817.5 1120.1  United States 150.28 128.61 199.5 161 190  Turkey 75.16 74.07 143 118 175.2  Saudi Arabia 77.75 72.95 69.1 58.5 72.2  Russia 60.12 67.50 76.7 81.9 73.3  United Arab Emirates 67.60 63.37 60.9 58.1 77.1  Egypt 56.68 53.43 36 47.8 57.3  Indonesia 41.00 32.75 55 52.3 68  United Kingdom 31.75 27.35 22.6 21.1 23.4 Other Persian Gulf Countries 24.10 21.97 22 19.9 24.6  Japan 21.85 18.50 −30.1 7.6 21.3  South Korea 18.83 15.87 15.5 12.1 17.5  Vietnam 15.08 14.36 100.8 77 92.2  Thailand 7.33 6.28 107.4 80.9 140.1 Total 1466.86 1770.71 2786.12 2477.7 3126.1 Other Countries 251.6 254.0 390.4 393.5 450.7 World Total 1718.46 2024.71 3176.52 2871.2 3576.8 Gold extraction is most economical in large, easily mined deposits. Ore grades as little as 0.5 parts per million (ppm) can be economical. Typical ore grades in open-pit mines are 1–5 ppm; ore grades in underground or hard rock mines are usually at least 3 ppm. Because ore grades of 30 ppm are usually needed before gold is visible to the naked eye, in most gold mines the gold is invisible. The average gold mining and extraction costs were about $317 per troy ounce in 2007, but these can vary widely depending on mining type and ore quality; global mine production amounted to 2,471.1 tonnes.[105] After initial production, gold is often subsequently refined industrially by the Wohlwill process which is based on electrolysis or by the Miller process, that is chlorination in the melt. The Wohlwill process results in higher purity, but is more complex and is only applied in small-scale installations.[106][107] Other methods of assaying and purifying smaller amounts of gold include parting and inquartation as well as cupellation, or refining methods based on the dissolution of gold in aqua regia.[108] Consumption The consumption of gold produced in the world is about 50% in jewelry, 40% in investments, and 10% in industry.[9][109] According to World Gold Council, China is the world's largest single consumer of gold in 2013 and toppled India for the first time with Chinese consumption increasing by 32 percent in a year, while that of India only rose by 13 percent and world consumption rose by 21 percent. Unlike India where gold is mainly used for jewelry, China uses gold for manufacturing and retail.[110] Pollution Further information: Mercury cycle and International Cyanide Management Code Gold production is associated with contribution to hazardous pollution.[111][112] Low-grade gold ore may contain less than one ppm gold metal; such ore is ground and mixed with sodium cyanide to dissolve the gold. Cyanide is a highly poisonous chemical, which can kill living creatures when exposed in minute quantities. Many cyanide spills[113] from gold mines have occurred in both developed and developing countries which killed aquatic life in long stretches of affected rivers. Environmentalists consider these events major environmental disasters.[114][115] Thirty tons of used ore is dumped as waste for producing one troy ounce of gold.[116] Gold ore dumps are the source of many heavy elements such as cadmium, lead, zinc, copper, arsenic, selenium and mercury. When sulfide-bearing minerals in these ore dumps are exposed to air and water, the sulfide transforms into sulfuric acid which in turn dissolves these heavy metals facilitating their passage into surface water and ground water. This process is called acid mine drainage. These gold ore dumps are long term, highly hazardous wastes second only to nuclear waste dumps.[116] It was once common to use mercury to recover gold from ore, but today the use of mercury is largely limited to small-scale individual miners.[117] Minute quantities of mercury compounds can reach water bodies, causing heavy metal contamination. Mercury can then enter into the human food chain in the form of methylmercury. Mercury poisoning in humans causes incurable brain function damage and severe retardation. Gold extraction is also a highly energy intensive industry, extracting ore from deep mines and grinding the large quantity of ore for further chemical extraction requires nearly 25 kWh of electricity per gram of gold produced.[118] Monetary use   Two golden 20 kr coins from the Scandinavian Monetary Union, which was based on a gold standard. The coin to the left is Swedish and the right one is Danish. Gold has been widely used throughout the world as money,[119] for efficient indirect exchange (versus barter), and to store wealth in hoards. For exchange purposes, mints produce standardized gold bullion coins, bars and other units of fixed weight and purity. The first known coins containing gold were struck in Lydia, Asia Minor, around 600 BC.[82] The talent coin of gold in use during the periods of Grecian history both before and during the time of the life of Homer weighed between 8.42 and 8.75 grams.[120] From an earlier preference in using silver, European economies re-established the minting of gold as coinage during the thirteenth and fourteenth centuries.[121] Bills (that mature into gold coin) and gold certificates (convertible into gold coin at the issuing bank) added to the circulating stock of gold standard money in most 19th century industrial economies. In preparation for World War I the warring nations moved to fractional gold standards, inflating their currencies to finance the war effort. Post-war, the victorious countries, most notably Britain, gradually restored gold-convertibility, but international flows of gold via bills of exchange remained embargoed; international shipments were made exclusively for bilateral trades or to pay war reparations. After World War II gold was replaced by a system of nominally convertible currencies related by fixed exchange rates following the Bretton Woods system. Gold standards and the direct convertibility of currencies to gold have been abandoned by world governments, led in 1971 by the United States' refusal to redeem its dollars in gold. Fiat currency now fills most monetary roles. Switzerland was the last country to tie its currency to gold; it backed 40% of its value until the Swiss joined the International Monetary Fund in 1999.[122] Central banks continue to keep a portion of their liquid reserves as gold in some form, and metals exchanges such as the London Bullion Market Association still clear transactions denominated in gold, including future delivery contracts. Today, gold mining output is declining.[123] With the sharp growth of economies in the 20th century, and increasing foreign exchange, the world's gold reserves and their trading market have become a small fraction of all markets and fixed exchange rates of currencies to gold have been replaced by floating prices for gold and gold future contract. Though the gold stock grows by only 1 or 2% per year, very little metal is irretrievably consumed. Inventory above ground would satisfy many decades of industrial and even artisan uses at current prices. The gold proportion (fineness) of alloys is measured by karat (k). Pure gold (commercially termed fine gold) is designated as 24 karat, abbreviated 24k. English gold coins intended for circulation from 1526 into the 1930s were typically a standard 22k alloy called crown gold,[124] for hardness (American gold coins for circulation after 1837 contain an alloy of 0.900 fine gold, or 21.6 kt).[125] Although the prices of some platinum group metals can be much higher, gold has long been considered the most desirable of precious metals, and its value has been used as the standard for many currencies. Gold has been used as a symbol for purity, value, royalty, and particularly roles that combine these properties. Gold as a sign of wealth and prestige was ridiculed by Thomas More in his treatise Utopia. On that imaginary island, gold is so abundant that it is used to make chains for slaves, tableware, and lavatory seats. When ambassadors from other countries arrive, dressed in ostentatious gold jewels and badges, the Utopians mistake them for menial servants, paying homage instead to the most modestly dressed of their party. The ISO 4217 currency code of gold is XAU.[126] Many holders of gold store it in form of bullion coins or bars as a hedge against inflation or other economic disruptions, though its efficacy as such has been questioned; historically, it has not proven itself reliable as a hedging instrument.[127] Modern bullion coins for investment or collector purposes do not require good mechanical wear properties; they are typically fine gold at 24k, although the American Gold Eagle and the British gold sovereign continue to be minted in 22k (0.92) metal in historical tradition, and the South African Krugerrand, first released in 1967, is also 22k (0.92).[128] The special issue Canadian Gold Maple Leaf coin contains the highest purity gold of any bullion coin, at 99.999% or 0.99999, while the popular issue Canadian Gold Maple Leaf coin has a purity of 99.99%. In 2006, the United States Mint began producing the American Buffalo gold bullion coin with a purity of 99.99%. The Australian Gold Kangaroos were first coined in 1986 as the Australian Gold Nugget but changed the reverse design in 1989. Other modern coins include the Austrian Vienna Philharmonic bullion coin and the Chinese Gold Panda. Price Further information: Gold as an investment   Gold price history in 1960–2011 As of September 2017, gold is valued at around $42 per gram ($1,300 per troy ounce). Like other precious metals, gold is measured by troy weight and by grams. The proportion of gold in the alloy is measured by karat (k), with 24 karat (24k) being pure gold, and lower karat numbers proportionally less. The purity of a gold bar or coin can also be expressed as a decimal figure ranging from 0 to 1, known as the millesimal fineness, such as 0.995 being nearly pure. The price of gold is determined through trading in the gold and derivatives markets, but a procedure known as the Gold Fixing in London, originating in September 1919, provides a daily benchmark price to the industry. The afternoon fixing was introduced in 1968 to provide a price when US markets are open.[129] History Historically gold coinage was widely used as currency; when paper money was introduced, it typically was a receipt redeemable for gold coin or bullion. In a monetary system known as the gold standard, a certain weight of gold was given the name of a unit of currency. For a long period, the United States government set the value of the US dollar so that one troy ounce was equal to $20.67 ($0.665 per gram), but in 1934 the dollar was devalued to $35.00 per troy ounce ($0.889/g). By 1961, it was becoming hard to maintain this price, and a pool of US and European banks agreed to manipulate the market to prevent further currency devaluation against increased gold demand.[130] On 17 March 1968, economic circumstances caused the collapse of the gold pool, and a two-tiered pricing scheme was established whereby gold was still used to settle international accounts at the old $35.00 per troy ounce ($1.13/g) but the price of gold on the private market was allowed to fluctuate; this two-tiered pricing system was abandoned in 1975 when the price of gold was left to find its free-market level.[citation needed]Central banks still hold historical gold reserves as a store of value although the level has generally been declining.[citation needed] The largest gold depository in the world is that of the U.S. Federal Reserve Bank in New York, which holds about 3%[131] of the gold known to exist and accounted for today, as does the similarly laden U.S. Bullion Depository at Fort Knox. In 2005 the World Gold Council estimated total global gold supply to be 3,859 tonnes and demand to be 3,754 tonnes, giving a surplus of 105 tonnes.[132] After 15 August 1971 Nixon shock, the price began to greatly increase,[133] and between 1968 and 2000 the price of gold ranged widely, from a high of $850 per troy ounce ($27.33/g) on 21 January 1980, to a low of $252.90 per troy ounce ($8.13/g) on 21 June 1999 (London Gold Fixing).[134] Prices increased rapidly from 2001, but the 1980 high was not exceeded until 3 January 2008, when a new maximum of $865.35 per troy ounce was set.[135] Another record price was set on 17 March 2008, at $1023.50 per troy ounce ($32.91/g).[135] In late 2009, gold markets experienced renewed momentum upwards due to increased demand and a weakening US dollar.[citation needed] On 2 December 2009, gold reached a new high closing at $1,217.23.[136] Gold further rallied hitting new highs in May 2010 after the European Union debt crisis prompted further purchase of gold as a safe asset.[137][138] On 1 March 2011, gold hit a new all-time high of $1432.57, based on investor concerns regarding ongoing unrest in North Africa as well as in the Middle East.[139] From April 2001 to August 2011, spot gold prices more than quintupled in value against the US dollar, hitting a new all-time high of $1,913.50 on 23 August 2011,[140] prompting speculation that the long secular bear market had ended and a bull market had returned.[141] However, the price then began a slow decline towards $1200 per troy ounce in late 2014 and 2015. Other applications Jewelry   Moche gold necklace depicting feline heads. Larco Museum Collection, Lima, Peru. Because of the softness of pure (24k) gold, it is usually alloyed with base metals for use in jewelry, altering its hardness and ductility, melting point, color and other properties. Alloys with lower karat rating, typically 22k, 18k, 14k or 10k, contain higher percentages of copper or other base metals or silver or palladium in the alloy.[23] Nickel is toxic, and its release from nickel white gold is controlled by legislation in Europe.[23] Palladium-gold alloys are more expensive than those using nickel.[142] High-karat white gold alloys are more resistant to corrosion than are either pure silver or sterling silver. The Japanese craft of Mokume-gane exploits the color contrasts between laminated colored gold alloys to produce decorative wood-grain effects. By 2014, the gold jewelry industry was escalating despite a dip in gold prices. Demand in the first quarter of 2014 pushed turnover to $23.7 billion according to a World Gold Council report. Gold solder is used for joining the components of gold jewelry by high-temperature hard soldering or brazing. If the work is to be of hallmarking quality, the gold solder alloy must match the fineness (purity) of the work, and alloy formulas are manufactured to color-match yellow and white gold. Gold solder is usually made in at least three melting-point ranges referred to as Easy, Medium and Hard. By using the hard, high-melting point solder first, followed by solders with progressively lower melting points, goldsmiths can assemble complex items with several separate soldered joints. Gold can also be made into thread and used in embroidery. Electronics Only 10% of the world consumption of new gold produced goes to industry,[9] but by far the most important industrial use for new gold is in fabrication of corrosion-free electrical connectors in computers and other electrical devices. For example, according to the World Gold Council, a typical cell phone may contain 50 mg of gold, worth about 50 cents. But since nearly one billion cell phones are produced each year, a gold value of 50 cents in each phone adds to $500 million in gold from just this application.[143] Though gold is attacked by free chlorine, its good conductivity and general resistance to oxidation and corrosion in other environments (including resistance to non-chlorinated acids) has led to its widespread industrial use in the electronic era as a thin-layer coating on electrical connectors, thereby ensuring good connection. For example, gold is used in the connectors of the more expensive electronics cables, such as audio, video and USB cables. The benefit of using gold over other connector metals such as tin in these applications has been debated; gold connectors are often criticized by audio-visual experts as unnecessary for most consumers and seen as simply a marketing ploy. However, the use of gold in other applications in electronic sliding contacts in highly humid or corrosive atmospheres, and in use for contacts with a very high failure cost (certain computers, communications equipment, spacecraft, jet aircraft engines) remains very common.[144] Besides sliding electrical contacts, gold is also used in electrical contacts because of its resistance to corrosion, electrical conductivity, ductility and lack of toxicity.[145] Switch contacts are generally subjected to more intense corrosion stress than are sliding contacts. Fine gold wires are used to connect semiconductor devices to their packages through a process known as wire bonding. The concentration of free electrons in gold metal is 5.91×1022 cm−3.[146] Gold is highly conductive to electricity, and has been used for electrical wiring in some high-energy applications (only silver and copper are more conductive per volume, but gold has the advantage of corrosion resistance). For example, gold electrical wires were used during some of the Manhattan Project's atomic experiments, but large high-current silver wires were used in the calutron isotope separator magnets in the project. It is estimated that 16% of the world's gold and 22% of the world's silver is contained in electronic technology in Japan.[147] Medicine Metallic and gold compounds have long been used for medicinal purposes. Gold, usually as the metal, is perhaps the most anciently administered medicine (apparently by shamanic practitioners)[148] and known to Dioscorides.[149][150] In medieval times, gold was often seen as beneficial for the health, in the belief that something so rare and beautiful could not be anything but healthy. Even some modern esotericists and forms of alternative medicine assign metallic gold a healing power. In the 19th century gold had a reputation as a "nervine", a therapy for nervous disorders. Depression, epilepsy, migraine, and glandular problems such as amenorrhea and impotence were treated, and most notably alcoholism (Keeley, 1897).[151] The apparent paradox of the actual toxicology of the substance suggests the possibility of serious gaps in the understanding of the action of gold in physiology.[152] Only salts and radioisotopes of gold are of pharmacological value, since elemental (metallic) gold is inert to all chemicals it encounters inside the body (i.e., ingested gold cannot be attacked by stomach acid). Some gold salts do have anti-inflammatory properties and at present two are still used as pharmaceuticals in the treatment of arthritis and other similar conditions in the US (sodium aurothiomalate and auranofin). These drugs have been explored as a means to help to reduce the pain and swelling of rheumatoid arthritis, and also (historically) against tuberculosis and some parasites.[153] Gold alloys are used in restorative dentistry, especially in tooth restorations, such as crowns and permanent bridges. The gold alloys' slight malleability facilitates the creation of a superior molar mating surface with other teeth and produces results that are generally more satisfactory than those produced by the creation of porcelain crowns. The use of gold crowns in more prominent teeth such as incisors is favored in some cultures and discouraged in others. Colloidal gold preparations (suspensions of gold nanoparticles) in water are intensely red-colored, and can be made with tightly controlled particle sizes up to a few tens of nanometers across by reduction of gold chloride with citrate or ascorbate ions. Colloidal gold is used in research applications in medicine, biology and materials science. The technique of immunogold labeling exploits the ability of the gold particles to adsorb protein molecules onto their surfaces. Colloidal gold particles coated with specific antibodies can be used as probes for the presence and position of antigens on the surfaces of cells.[154] In ultrathin sections of tissues viewed by electron microscopy, the immunogold labels appear as extremely dense round spots at the position of the antigen.[155] Gold, or alloys of gold and palladium, are applied as conductive coating to biological specimens and other non-conducting materials such as plastics and glass to be viewed in a scanning electron microscope. The coating, which is usually applied by sputtering with an argon plasma, has a triple role in this application. Gold's very high electrical conductivity drains electrical charge to earth, and its very high density provides stopping power for electrons in the electron beam, helping to limit the depth to which the electron beam penetrates the specimen. This improves definition of the position and topography of the specimen surface and increases the spatial resolution of the image. Gold also produces a high output of secondary electrons when irradiated by an electron beam, and these low-energy electrons are the most commonly used signal source used in the scanning electron microscope.[156] The isotope gold-198 (half-life 2.7 days) is used in nuclear medicine, in some cancer treatments and for treating other diseases.[157][158] Cuisine   Cake with gold decoration served at the Amstel Hotel, Amsterdam Gold can be used in food and has the E number 175.[159] In 2016, the European Food Safety Authority published an opinion on the re-evaluation of gold as a food additive. Concerns included the possible presence of minute amounts of gold nanoparticles in the food additive, and that gold nanoparticles have been shown to be genotoxic in mammalian cells in vitro.[160] Gold leaf, flake or dust is used on and in some gourmet foods, notably sweets and drinks as decorative ingredient.[161] Gold flake was used by the nobility in medieval Europe as a decoration in food and drinks,[162] in the form of leaf, flakes or dust, either to demonstrate the host's wealth or in the belief that something that valuable and rare must be beneficial for one's health.[citation needed] Danziger Goldwasser (German: Gold water of Danzig) or Goldwasser (English: Goldwater) is a traditional German herbal liqueur[163] produced in what is today Gdańsk, Poland, and Schwabach, Germany, and contains flakes of gold leaf. There are also some expensive (c. $1000) cocktails which contain flakes of gold leaf. However, since metallic gold is inert to all body chemistry, it has no taste, it provides no nutrition, and it leaves the body unaltered.[164] Vark is a foil composed of a pure metal that is sometimes gold,[165] and is used for garnishing sweets in South Asian cuisine. Miscellanea   Mirror for the James Webb Space Telescope coated in gold to reflect infrared light Gold produces a deep, intense red color when used as a coloring agent in cranberry glass. In photography, gold toners are used to shift the color of silver bromide black-and-white prints towards brown or blue tones, or to increase their stability. Used on sepia-toned prints, gold toners produce red tones. Kodak published formulas for several types of gold toners, which use gold as the chloride.[166] Gold is a good reflector of electromagnetic radiation such as infrared and visible light, as well as radio waves. It is used for the protective coatings on many artificial satellites, in infrared protective faceplates in thermal-protection suits and astronauts' helmets, and in electronic warfare planes such as the EA-6B Prowler. Gold is used as the reflective layer on some high-end CDs. Automobiles may use gold for heat shielding. McLaren uses gold foil in the engine compartment of its F1 model.[167] Gold can be manufactured so thin that it appears semi-transparent. It is used in some aircraft cockpit windows for de-icing or anti-icing by passing electricity through it. The heat produced by the resistance of the gold is enough to prevent ice from forming.[168] Gold is attacked by and dissolves in alkaline solutions of potassium or sodium cyanide, to form the salt gold cyanide—a technique that has been used in extracting metallic gold from ores in the cyanide process. Gold cyanide is the electrolyte used in commercial electroplating of gold onto base metals and electroforming. Gold chloride (chloroauric acid) solutions are used to make colloidal gold by reduction with citrate or ascorbate ions. Gold chloride and gold oxide are used to make cranberry or red-colored glass, which, like colloidal gold suspensions, contains evenly sized spherical gold nanoparticles.[169] Gold, when dispersed in nanoparticles, can act as a heterogeneous catalyst of chemical reactions. Toxicity Pure metallic (elemental) gold is non-toxic and non-irritating when ingested[170] and is sometimes used as a food decoration in the form of gold leaf.[171] Metallic gold is also a component of the alcoholic drinks Goldschläger, Gold Strike, and Goldwasser. Metallic gold is approved as a food additive in the EU (E175 in the Codex Alimentarius). Although the gold ion is toxic, the acceptance of metallic gold as a food additive is due to its relative chemical inertness, and resistance to being corroded or transformed into soluble salts (gold compounds) by any known chemical process which would be encountered in the human body. Soluble compounds (gold salts) such as gold chloride are toxic to the liver and kidneys. Common cyanide salts of gold such as potassium gold cyanide, used in gold electroplating, are toxic by virtue of both their cyanide and gold content. There are rare cases of lethal gold poisoning from potassium gold cyanide.[172][173] Gold toxicity can be ameliorated with chelation therapy with an agent such as dimercaprol. Gold metal was voted Allergen of the Year in 2001 by the American Contact Dermatitis Society; gold contact allergies affect mostly women.[174] Despite this, gold is a relatively non-potent contact allergen, in comparison with metals like nickel.[175] A sample of the fungus Aspergillus niger was found growing from gold mining solution; and was found to contain cyano metal complexes, such as gold, silver, copper iron and zinc. The fungus also plays a role in the solubilization of heavy metal sulfides.[176] See also   Iron pyrite or "fool's gold" Bulk leach extractable gold Chrysiasis (dermatological condition) Commodity fetishism (Marxist economic theory) Digital gold currency GFMS consultancy Gold fingerprinting Gold phosphine complex Gold Prospectors Association of America List of countries by gold production Mining in Roman Britain Prospecting Tumbaga Iron pyrite References   Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". 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