I have the chance to pick up a nice copper coin but it has black spots on it. In the fields, around and on the raised details, etc. I don’t buy coins like this so can these black spots be removed? Is conservation by a professional recommended? Thanks for your help in advance.
I believe conservation can be achieved but depending upon the coin, the cost of such might be prohibitive.......
What coin is it? Black spots can obviously lower the grade of a coin but I've seen straight-graded copper with these spots, albeit they're quite light while still noticeable. One more question: do you have pictures of the coin?
No photos as it’s not mine. It’s a solid mid grade coin on the scale of 70. The black spots don’t lower the grade as it’s a details grade with them.
Depending on the coin. Rarity and condition after the conservation VS price...Can you buy the same coin without the issue for the same $$? Keeping in mind, I'm under the impression that COPPER once it has an issue, it's always going to have said issue and years down the road could show up again.
While I am not a fan of AI this is what AI says: "Black spots on copper coins are typically a form of oxidation or corrosion, often referred to as carbon spots, though they don't necessarily contain carbon. These spots are often caused by sulfur compounds reacting with the copper in the coin, especially when the coin's alloy has uneven copper distribution. While commonly called carbon spots, they are more accurately described as copper spots or sulfur spots." If this is true, I don't think any conservation or masking of these spots is going to help as the coin is permanently damaged from the corrosion. If a company can reverse corrosion and make the coin acceptable to graders and not details, that would be a multi million dollar process.
Thanks all. I decided against the coin that this question was about. I did buy another coin that I’ve always wanted. I’ll post after I receive it.
