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Silver oxidises over time making it look black. Moisture from the human body can speed up this process

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Q: Why do silver coins become black on keeping for long time?
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Related questions

When were the US silver coins last used?

in the US silver coins were last used in 1964, the reason behind the overhaul of coins of which several were heavily made with silver, was available quantities of this precious metal were rapidly decreasing and keeping up with demand for new coins increasingly difficult


Do banks hold rare coins?

Generally not. Old circulated silver coins occasionally turn up, but banks don't make a point of keeping rare coins in stock.


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Are casino coins the same as silver coins from mint?

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What coins are silver in 1974 and 1975 Proof Coins of Belize?

There were proof sets made in 1974 and 1975 where all 8 of the coins were silver, and proof sets made during those years when none of them were silver. Assuming that your coins are in a set, check the 1 Cent coin - if it looks silver, then all the coins in the set are silver; if it looks bronze, then none of the coins in the set are silver.


When were coins 100 percent silver?

Just recently with the advent of bullion coins such as the American Silver Eagle. Coins intended for circulation were never 100% silver because silver is simply too soft of a metal for coinage. They were 90% silver in American coins until 1964 for dimes, quarters and half dollars, but other than bullion coins, no coins are made of 100% silver.


Which British coins are made of real silver?

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Are jamacian coins silver?

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What coins are made of silver in the United states?

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Are five dollar desert storm coins pure silver?

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