Hi. The 1 cent in my 2000 silver proof set has red spots on the obverse. Any idea what might have caused this? Just wondering.
Copper is a very reactive metal. It tarnishes quite easily, when it comes in contact with any impurities in the air. Proof cents are very succeptible to spotting. Even talking over one, can transfer small moisture droplets onto the surface of the coin. Over time these spots can become darker, and more noticeable. The impurities may have been there before it left the Mint, or it may have something to do with the way it has been stored since it left the Mint. Make sure you store your coins in a cool, dry place, with low humidity, to reduce the chance of spotting or toning.
interesting. It came from the mint looking like that. & it's sealed in the proof set case. Guess it got contaminated at the mint somehow.
