Numism > Help For the New Ancient Coin Collector

terrible gold fake... What do you think!

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Mark Farrell:
Pat,

Thanks for the quick and thorough reply! This matter is very important to me because I clean coins. Understanding the composition is pretty important because without knowing the metal, sometimes it is hard to know how far I should go.

It was been pretty simple on the AE 3s and 4s I started with, but as I work on larger coins, primarily provincials from the Balkans and Asia Minor, it has gotten more complicated. More fun, mind you, but harder.

Is it a general rule of thumb, then, that if a coin is greater than or equal to 18 mm diameter (give or take) AND a provincial from the Balkans, then it is likely the coin is brass? Is there a general time frame when this rule does not apply, e.g., during or after the reign of emperor X?

I further understand that this rule does not apply to coins minted in Asia Minor. Right?

Finally, regarding brass coin production in the Balkans... Is there an underying reason for this? Perhaps greater availability of zinc locally than tin? Just curious on this one, not a truly operational question...

Thanks again, Pat (and Curtis) for the information,

Mark

slokind:
First, about the sizes.  Depending on how thin it is and how big a wad they started with, a copper coin might be wider than 18mm; they weren't fussy about precise weights.  The next-to-smallest, perhaps a dyassarion, averages D=18mm.  A better rule of thumb (since no one wants to hurt a perfectly good protective patina!) is that the coppers don't have that pit or dimple (see another thread on that) in the center; it CAN be struck into non-existence but very rarely is such the case on both sides, and the effort of a cosmetic conservator to fill it is usually discernible.  But the heirs and empresses, when they are given issues larger than the coppers but not as large as the augustus, have coins averaging 23mm and about 7g (approximations) that do have the pits and (where visible) are of brass.  And the coins weighing about 9g to about 14g that measure about 25mm to 29mm that where marked have D, D<, or E on the reverse (not marked at Nicopolis) look and feel like brass where not thickly patinated.  The Faustina that I posted isn't REALLY patinated, by my standards; I doubted even its genuineness until I got another from the same die that was.  Like Macedonia, Thrace produced lots of metal ores in antiquity.  Mere internet browsing taught me that there is still a big zinc operation at Plovdiv (Philippopolis); the museums are full of Thracian metalwork, so much that after a few of them I decided that ancient Thracians were true Tolkienian dwarves.  Notice what unscientific statements those are; I keep trying to find real research.  The cold war left a gap in the communication of research that I may not live to see closed.  One more attachment, which would have a  :Greek_Gamma: on it if marked.  At Marcianopolis there is one for him that does have a gamma.  The green is hard green patina.  The pits are plain .  The metal is yellow.  Pat L.

Mark Farrell:
Thanks, Pat.

Yes, I remember the dimples  :)

Your examples were also very helpful -- I'm traveling now but believe when I return home that a Gordian III of Viminacium I just purchased can confirm for me the brass content. I thought it was perhaps just inappropriately cleaned, which could leave brassy tones on the highlights. Now I suspect the rascal is brass through and through. That's from a vendor photo and once I have the coin in hand, many questions I had previously will be answered!

Great info, Pat, and if you ever dig up more on mining, etc., in Balkan region, let me know.

Thanks again,

Mark

Chiz...:
WOW.. Thanks for all the good info!!!  There were several things that got me with this coin.  One was the "over brassy" look since the only other 2 pics I can find of the coin didn't have any brass at all showing.  Next was the "grainy look" as well as the "porous look" of the brass itself, I suppose the person that had it before me just overcleaned it like most of you have said. Last was the Dimples  :-[  I know now...

Thanks Pat for the insight as to the metal content and the other great info!!!  You people are making it fun to learn this hobby and it is much appreciated!!

~ Chiz

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