Identifying a Cast Counterfeit

Posted by Skip Fazzari, Authentication Consultant to NGC on 9/21/2007

Even a cast counterfeit can be deceptive when it has been improperly cleaned. Skip Fazzari describes the warning signs to watch out for.

In the early 70s, one top authenticator claimed that he could have a cast coin made that would defy detection. I said, “Prove it,” and waited. The months passed and I waited some more. Finally, the authenticator came to the lab with his piece. As I recall, it was a silver colored medal a little larger than a Morgan dollar. The piece looked really good to the naked eye – a “professional job.” It had semi-prooflike surfaces and a sharp, detailed design. I could tell he was extremely pleased by my first impression. But even that long ago, I didn’t authenticate coins by naked eye at the lab. I wanted to examine the medal with my Nikon scope. As soon as I did, I realized that the piece was not deceptive at all. There were microscopic holes and a crystalline pattern typical of castings all over its surface.

Casting methods have improved since then. Recently, I was asked to examine an 1889-CC Morgan dollar that had been moderately polished. The abrasion had made it look suspicious to the submitter. My first impression was that the coin was genuine. I could see definite signs of metal flow from the denticals; a characteristic of coins struck using dies. For this reason, I was not too concerned with the rounded edges seen on the star points, letters, and relief. Although many counterfeit coins share this characteristic – a rounded, “soft” relief; heavy cleaning will also cause the design of genuine coins to flatten out and become rounded. Authenticating this coin would take some close scrutiny using a stereo microscope.

First, I checked the Carson City mintmark to confirm that it was not added. Each “C” was identical and there was no trace of the seam usually found on coins with an added mintmark (where it joins the field). The cleaning had affected the sharpness of the “CC.” It was rounded off at its edges. The coin also had a dark outline visible around the mintmark, legend, and relief design that is often found on heavily abraded coins. It indicates areas that the mechanical process being used to alter the coin’s surface was unable to reach. So far, everything indicated a harshly cleaned, genuine coin.

Further examination (at 10X to 16X) revealed some tiny holes in the coin’s surface along with lumps of extraneous metal that were not part of its design, especially at the vertical sides of some letters in the legend. The coin was turning out to be a cast counterfeit — something totally unexpected! Although genuine coins (particularly those with environmental damage) can have tiny holes and lumps of extraneous metal on their surface, be wary of those with holes and lumps that are smooth and rounded. Generally, when these defects are seen on a genuine coin, they will have an irregular shape. Raised lumps on genuine coins often have microscopic metal flow on their sides. Be sure to check the sides of the letters and numerals of the coins you examine. Lumpy edges or areas that have been tooled to remove these defects should raise your suspicions.

Although a coin like the one I describe here is too impaired to be graded at NGC, its owner made the wise decision to have it checked for authenticity. If it were genuine, he could have had it graded and encapsulated at NCS. This coin proved that even a cast counterfeit can be quite deceptive when it has been improperly cleaned!

This article previously featured in Numismatic News.

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