The zinc core has a lower melting point than the very thin copper plating, so if you carefully heat the coin until the zinc liquifies, the surface...
The eroded copper layer is a characteristic of a coin that was exposed to an acidic environment. The copper reacted before the Copper/Nickel...
Make sure you can spot any cleaned coins. That will reduce the value.
It is definitely not a proof. Just a 1973 business strike from Philadelphia
They are die chips. Interesting, but they really don't have any extra value. Still, cool and I would keep it if I got it in change.
The coins in the OP are not errors. They were squeezed /pressed after they left the mint, as @thomas mozzillo said. They are damaged and only...
Have an XRF analysis done. That should pick up any silver However, I wouldn't waste your time and money. I see environmental damage, not an off...
@Collecting Nut He said Die Chip. It's always best to finish your first cup of coffee before answering posts. I have a bad habit of doing that,...
Nice example of a clashed die. It's not worth much, but if I got this in change, I would keep it. It's definitely 2x2 worthy IMO
1973 Proof coins were minted in San Francisco. I don’t see an S mm on your pictures (but hard to tell with your pics). If there’s no mm, it’s a...
Sorry but it is not an error. It suffered environmental damage. Your coin looks like it was buried in the ground. Not sure where you're getting...
It's a misaligned die, not an off center strike. No real premium over face value. Take some time and look it up on error-ref.com
The reeding on an improperly annealed coin will look like a normally minted coin. The edge of an environmentally damaged coin will have a dark...
Environmental damage. Edge is the same color as the surfaces
Most discolored coins found in circulation are going to be environmental damage. Check the coin talk archives for some threads that discuss how...
Not if the "raised lines" aren't raised lines. The low points are not the original surface, they from being pressed in or some sort of impact,...
The mottled appearance looks like environmental damage. What does the edge look like?
The U.S. Mint started adding the P mm to nickels, dimes, quarters and halves in 1980. Prior to that all Philly minted coins had no mm (except...
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It doesn't appear as if there was anything significant that was duso!ved, or eaten away. Just some chemical reaction that darkened the surface of...
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