There are several different kinds of doubling that can be found on coins -- whether it's caused by a doubled image on the die used to stamp the coin, or caused by excessive wear or damage to the die, or caused by the coin being actually stamped twice, or caused by other reasons.
There is an excellent web page that explains the different kinds of doubling (with pictures) here : http://koinpro.tripod.com/Articles/OtherFormsOfDoubling.htm
Dan Moore The Working Man's Rare Coins http://www.workingmancoins.com
There's a picture at the Related Link.
The easy way to see one is, type in 1955 Double Die on your browser and click images.
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You coin could be a mint error or it could be one with one side sanded off. I would suggest you take it to a coin shop and have them look at it to determine what it is.
The US has never made any gold one cent coins. It may look like gold (toning) or may have been gold plated, the counter stamped date or plating was not done by the US Mint and adds no value at all to the coin. The coin is worth one cent unless you find someone that wants it.
There's a picture at the Related Link.
The easy way to see one is, type in 1955 Double Die on your browser and click images.
It has doubling in liberty and in god we trust and there only 2 unowned
It looks exactly the same as the 2010 or 2012 penny.
The US coin looks very much like a modern US penny
It was so different because it was double stamped. That's is about all I know. That's what makes it worth a lot more today.
It is silver
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It's worth a whole cent. The fingerprint isn't stamped in but was etched when someone handled it with dirty fingers. Over time, the oils from your skin will react with the metal in the coin, actually eating into the surface of the coin, which may make it look like the fingerprint was stamped into the coin. This is considered damage to the coin and can easily make the coin worthless to collectors.
All British Pennies from 1982 to 2008 look pretty much the same as the Penny shown at the link below.
It looks exactly like the US cent.
Look at it under a lens. If you are still not sure then take it to a coin dealer and have them look at it.