Proper care and handling of copper coins

Rocelle writes: Under what circumstances will a full proof red penny undergo discoloration in a matter of days? Such a penny I bought for over USD3k was delivered to me in a coin album (packed in a cardboard material with plastic cover). I took a cursory look at it paying more attention to the writings on the coin and the album; kept it straight away in a closet, brought it out four days later to show my hubby. He noticed what he thought was a scratch.

I brought it back to the dealer, who said it was a “discoloration” but refused to give a refund as it was in a “perfect” condition when they packed it. He remarked that the seal was “loose” and someone in my family must have opened it and handled it. I maintain that there was no way that could have happened. Is it possible that the coin was “perfect” when they packed it; but for some reason (perhaps improper sealing), the coin came into contact with some chemicals in the album or packaging and had developed the discoloration within the next four days?

By the way, as he was examining the coin, the dealer handled it, wiped it with tissue and blew on it (as in exhaling gently). Does this constitute carelessness?

Improper handling, wiping and blowing on a coin isn’t careless, it’s abuse and reduces the coin’s value. It is unusual, but possible, for copper, a chemically reactive metal, not to have oxidized over a long or short period of time. Generally, original full red copper coins have been fortunate to have undergone oxidation that is essentially transparent. Unfortunately, most have been chemically treated in some way to restore the full red appearance, at least, for a short time.

Packaging copper in cardboard, canvas or heavy paper is counterproductive as those items contain sulfur, a great copper oxidizer. You would never store red copper coins near those materials. (A great way to create nice patina on red copper is store a red copper coin in a Kraft envelope, those little brown things, for three months or so.) Most destructive is to blow on a copper coin. Months later, little black spots will appear where the moisture from breath or saliva has reacted with the copper.

The best luck that I have had with full red coins is to store them in the old style 2 x 2 non-sulfur cardboard holder lined with cellophane. The cellophane seems to protect the coin. I’ve had full red cents from the 1920’s and 30’s stored in them for years without the coins oxidizing.

You mentioned that the coin was a “full proof”. “Proof” is a method of manufacture, not a statement of condition. Proof coins are minted and handled individually and struck multiple times vs. “business strikes” that are struck once and mass produced. Proofs are minted for collectors or, as in the early 19th century, for presentation. Proofs are graded in the same manner as regular mint strikes so it is possible for a proof to have evidence of handling, abuse or even wear.

I suggest that if you are interested in collecting copper and are first starting out, purchase red-brown or brown examples. They are less expensive and more likely to be original and, of course, you don’t have to worry about them oxidizing.