Science!
Poll No cheating via wikipedia/google!
Answer: None of them. With the exception of Uranium (lower, but density ~= gold), none of them are even close. In fact, gold is at LEAST 40% denser than the non-uranium elements listed in the poll. There are only a handful denser - most of them comically radioactive/unstable. Platinum and plutonium were the only ones I'd even heard of in use.
Why is this significant? It means that 24K (99.99% pure) gold is all but impossible to fake. All you have to do is weigh it and measure it - there's no way to make something even close to as dense without resorting to A) great expense and/or B) extreme radioactivity.
It also means that in the instance of gold coins any fake will either be A) much lighter weight or B) much larger in dimension. Often both, because of the large gap between gold's density and any other useful material.
Silver, on the other hand, is just slightly less dense than lead. Which makes for a pile of easy ways to make material cheaper than but difficult to discern from silver.
In fact, I bet if somebody wanted to sell you fake plutonium they'd start by using a lot of good 'ol inert gold. Well, maybe tungsten. But who has any of that lying around?
Answer: None of them. With the exception of Uranium (lower, but density ~= gold), none of them are even close. In fact, gold is at LEAST 40% denser than the non-uranium elements listed in the poll. There are only a handful denser - most of them comically radioactive/unstable. Platinum and plutonium were the only ones I'd even heard of in use.
Why is this significant? It means that 24K (99.99% pure) gold is all but impossible to fake. All you have to do is weigh it and measure it - there's no way to make something even close to as dense without resorting to A) great expense and/or B) extreme radioactivity.
It also means that in the instance of gold coins any fake will either be A) much lighter weight or B) much larger in dimension. Often both, because of the large gap between gold's density and any other useful material.
Silver, on the other hand, is just slightly less dense than lead. Which makes for a pile of easy ways to make material cheaper than but difficult to discern from silver.
In fact, I bet if somebody wanted to sell you fake plutonium they'd start by using a lot of good 'ol inert gold. Well, maybe tungsten. But who has any of that lying around?