How To Tell If A Coin Has Been Mounted In Jewelry

If genuine, these staters were made from gold of about 95% purity, which was the highest possible purity obtainable at the time.

Gold is soft. I find it almost impossible to believe that after 2,300 years, that so many of these coins have survived in such pristine condition.

Despite all third party assessments that such coins are genuine, I still have my doubts. Macedonian staters these days in this condition seem to be curiously more common than they were 50 years ago, (20 yrs old at the time), when I first took an interest in ancient coins.

They can be tested by XRF looking for trace elements, not gold.

My coin came from Spinks in London, in 1978. I still have all of the sales documentation and packaging, as well as the B&W polaroids.

I picked up this coin yesterday & posed a question about the raised bumps. (So far) the consensus is juxtaposed to flattened rims. Rather, the raised portions are the result of the coin being mounted in a bezel... but I suppose there is more then 1 way to mount a coin into jewelry.

There are many ways to mount a coin for jewllery.

Ancient coins are irregular in shape; jewellery-makers usually like symmetry, so an ancient coin might be "rounded". I own a small copper coin from Carrhae (Iraq), which some previous owner decided to make round by filing down the edges on one side.

The irregularity and thickness of your typical ancient coin usually means that "mounting" it is done via a mechanism not entirely unlike the mechanism used in the OP's picture of the slabbed coin: claws at three, four or five points holding the coin firmly in place. Except that in the case of jewellery, the claws are metal rather than plastic. This will create "dents" in the coin where the claws had grabbed on.

The other way such a coin might be mounted is by soldering on a loop or other attachment. "Solder" sounds harmless, but we're talking about jeweller's solder - made of metal that melts at a temperature only slightly lower than the coin itself. It doesn't come off with an ordinary household soldering iron. Nor will it simply "wash off" in strong acid. It's also usually of a high silver content, so looks paler than a pure-gold coin would normally look. Since the composition is different at a solder spot, they can cause a stain of tarnish or other discolouration, even on a gold coin. They also usually scuff up the coin at the point on the coin where the solder is attached using fine sandpaper, so the solder can get a better grip on the surface; this of course permanently damages the coin, eve if you could in theory get all the solder off.