Good Afternoon, As of today I have just about purchased the following gold coin. It is quite rare and I need it to further my collection. It is graded ms 64 by NGC. Whenever I view the coin straight it exhibits prroflike fields and no spots or dots of any kind. When I raise it to the light however it shows numerous spots. The spots appear dark reddish but I am not sure if they are copper spots or carbon spots. I am happy with how the coin looks regardless of the spots. I have been waiting a long time to purchase it and finding another is no easy task. My only concern is will the spotting increase and is damage to the coin possible? Granted the coin will be in a safety deposit box with no humidity in an intercept shield holder in addition to its ngc holder. Please any thoughts. I have researched extensively about copper and carbon spots and have read much about how carbon spots can damage a coin but I remain confused on this one. It is distressing me to a great degree any advice will be much appreciated.
I would say the spots are little more than evidence of the coin being original and never cleaned. I've got several gold coins in my collection with spots, this Czech piece being the most spotted. Color gradations and spotting on gold coins is not really a negative provided the coin still has a nice overall appealing appearance to it. On silver coins, that's a different story. If a coin has so much spotting that it looks like it was fished from a tar pit, generally I avoid the coin, --even if its a finest known specimen.
Thanks for the information Bruce, Do you believe the spots on my 50 franga here are carbon or copper? To me they appear dark red but I am not sure. Some say they are mint defects when byproducts such as sawdust hit the coin during manufacturing. Others say the spotting is due to irregular handling such as saliva on the coin. In any case will the spotting getting worse? P.S-what are your general thoughts on the coin?
Copper spots it looks like to me. Which is part of the metal itself not being fully uniform, some areas having a much higher content of copper and thus inclined to tone as any primarily copper alloy would over time.