About 16 years ago I bought a beautiful Ptolemaic tetradrachm at a coin show in Rochester, NY, pictured below (not slabbed at the time). The coin was attributed to Ptolemy VI Philometor, 180-145 BC, & cost me $400.00. At the time I knew virtually nothing about Greco-Egyptian coinage & sent the coin to David Sear in 2004 for his more detailed certificate of authenticity. The coin came back with a wealth of information & he attributed the coin to the "Aradus Mint (?)" in Phoenicia, with the "date 92 of the Aradian era = 168-167 BC." He graded the coin "good EF, an outstanding example of this scarce and interesting dated series", with no mention of horn silver. About 7 years ago I decided to liquidate most of my Greek coins & focus on Roman coins so I sent this coin to NGC for slabbing & it came back labeled horn silver, much to my surprise . The coin went to a Heritage auction where they made no mention of horn silver in the description & the coin sold for $2,185.00. I never saw anything on the coin that resembled horn silver, neither did David Sear, or David Michaels from Heritage. What do CoinTalk members think, horn silver not ?
Yes I see it on the reverse particularly around the eagle's head and in the oY before the beak. But it is so slight I wouldn't think to mention it. Nice coin btw
David, Thanks for your take on the coin. Apparently the buyer at the Heritage auction wasn't too concerned either.
I wouldnt think that as horn silver. horn silver is thick and sticks to the metal for example this nero coin has horn silver.
Hookman, Horn silver is another name for Silver Chloride (AgCl), an encrustation that can form on the surface of silver that's been exposed to Hydrogen Chloride (HCL) in burial. Sometimes it's difficult to differentiate from other encrustations. I think David hit the nail on the head, the horn silver on my coin was to slight to mention.
Domit_over, Your coin's horn silver is more obvious than mine was, but still not distracting. The good thing with horn silver is it doesn't get worse like "bronze disease".
I think they put the notation on the slab to explain the remnant staining on the surfaces. It was cleaned off quite successfully and virtually nothing remains but a shadow.
AL kowsky, That coin not mine unfortunately but I just found that as a good example to demo what horn silver means. But I have been told a positive thing about horn silver is that it generally a good indication of authenticity as it is hard to create and happens for ages in burial conditions. Also removing it sometimes not good idea as it exposes the uneven surfaces under that. Actually these Nero example I believe that someone did try to remove the horn silver but left part of it as it was risky to remove. You can see the other area of coin has uneven surfaces that seems to be result of horn silver removal.
The horn silver is so slight on the reverse that it seems silly to even have written it on the slab. Who cares really. The iridescent toning is gorgeous and the coin is minty. I would have paid what the coin hammered for. A beautiful piece. Well bought and well done!
ShannaS, I totally agree with you, & DomitLover makes a good point too, "generally a good indication of authenticity as it is hard to create".
Small comment from a chemist. HCl is hydrogen chloride, and in case that means little or nothing to most readers, HCl is a gas and when dissolved in water, is called hydrochloric acid, or for people who might buy it at the hardware store, muriatic acid.
horn silver of not come on it is 300 hundred years old, dont collect old coins every old coins has problems