Just sayin'. I know they're an "as made" thing, but I can't quite get past the fact that they look like a deep gouge in the coin, as though someone started to drill a hole in it and then quit. Discuss. I don't have any examples of this phenomenon, so feel free to post yours. (I've been casually browsing Seleucid and Ptolemaic AEs, as you can probably guess...)
What annoys me is the term, "centration dimple," because they don't have anything to do with centration. The indentations almost certainly resulted from lathe-turning of the flan to prepare it for striking. The best explanation about this technique of flan preparation can be found here at Classical Coins’ website. But they can certainly ruin a portrait. Here are some of my Gordian and Tranquillina marriage issues with some tragically-placed dimples: POW! Right in the empress's nose! Ouch! Gordy taking it on the chin! Boom! Right in Athena's chest! Apparently, he turned the other cheek!
They are interesting for the insight they provide in flan preparation, but as others have shown they sometimes spoil the design of the coin.
Here is the most pronounced example that I have, and on an otherwise fine example. I choose to see it as "production evidence" rather than a flaw, and that makes it interesting, rather than bothersome. That said, do I want them on all my coins? Nope! Herakles has no trouble putting in his ear drops! Kings of Macedon, Antigonos I Monophthalmos, Drachm Magnesia ad Maeandrum mint Obverse: Head of Herakles right, wearing lion skin. Reverse: Zeus Aëtophoros seated left; monogram in left field and below throne
FLAN PRODUCTION DIMPLES: Egypt Ptolemy IV 221-205 BC AE 37mm 42g Drachm Zeus-Ammon Eagle Tbolt SV 974 Egypt Ptolemy IV 221-205 BC AE 33mm 35g HemiDrachm Zeus-Ammon Eagle Tbolt Egypt Ptolemy III 245-222 BC AE 34mm 31g HemiDrachm Zeus-Ammon Eagle Tbolt Cornucopia XP Chi-Rho SV 965 Egypt Ptolemy II 285-274 BC AE Obol 20mm 6.7g Alex III Eagle Tbolt Plain SV 601 Egypt Ptolemy III Euergetes 246-222 BCE AE Chalkous 12.0mm 2.0g Zeus-Ammon Eagle Trident Svoronos 840 ex Righetti Collection Interesting that the above small 12mm / 2.0g flan had the dimple preparation. But this version did NOT use dimple preparation of the flan. Perhaps this process was later than this coin's mintage. Egypt Ptolemy II 285-274 BC AE 17mm Eagle Cornuc SV 762 Personally, I do not mind the dimples, and am fascinated at the innovative manufacturing process.
@Roman Collector - thanks for the correction, and the link. I edited the title, though I had already placed the misnomer in quotes. It doesn't bother me on that one, either, and I like the contrasting coloration of that. That is a spectacular looking coin with extremely attractive toning, and the dimple really "works" in this particular situation. Love it!
I've never owned a Zeus/Eagle Ptolemaic bronze, or for that matter, any Ptolemaic coins ... yet. I like the design - quite a bit - but it seems to me they overused it. And then there are the dimples. Prediction: I think this thread is possibly going to adjust my attitude slightly.
Hmm. I don't think "centration dimples" are found on these Macedonian drachms and tets. The flan manufacturing process was different. The two "dimples" on your coin have some other explanation.
There are centration dimples and then there are centration dimples. I assume they hit an air pocket in the flan and had to start over. Dealer's photo.
I think that right there is forensic proof of the invention of firearms a millennium or so earlier than previously believed. And Zeus lost the duel. Otherwise a handsome coin, though.
I will see if I can extract a .22 shell... Or perhaps Hera, in a fit of rage, decided to perform a bit of brain surgery.
I bought a small lot of Termessos Major coins and I found that many of them had these centration marks. Doesn't bother me a bit, it was perfectly normal at that time.
I do not see this as a dimple but suspect ordinary damage. I have never seen a dimple on a silver coin. I know there are many people who will not collect these coins because of the 'damage' and that is fine with me since it keeps the price down. I have seen a few with the dimple filled in and tooled over to produce a mint state and 'damage' free coin suitable for the most discerning perfectionist. I assume there are those who do not collect Chinese cash because of those pesky square holes???? The dimples are just part of what we call the fabric of the coin. Some like them round; others like them however they are. https://www.forumancientcoins.com/dougsmith/fabric.html Anyone else like these enough that they appreciate the difference between the dimples in the small photo below? Some of us not only accept dimples but we look deep into them and enjoy what we see.
This is something that has been perplexing me recently and I was going to raise this soon but lordmorcovan beat me to it. I have been buying coins from a large collection that was put together over 45 years. The coins range from virtually unidentifiable coins that were bought for cents 40 years ago to some rare and exceptional coins that sadly included some fakes that the forum has put me straight on. As the fakes are identified most are returned to dealers but in some cases the dealers are no longer around but fortunately the collector has morals and these won't surface again. The collection is now being appraised by a major auction house so my involvement is no more. There are thousands of coins and peppered through the collection are dozens of coins with such dimples. I have no problem with wear, damage or irregular flans or offset strikes as these are part of the coins history but these dimples looked too precise to me and given my experience with the fakes I decided to leave any of these well alone. At one time I even wondered if these were a mark from high pressure die casting but I didn't hold this opinion for long when I could see that the value of the coins would not justify expensive tooling. The comforting aspect of this thread to me is that these marks are quite contemporary and not potentially nefarious. Can someone explain about centration and why the dimples are there? As an engineer I can make some guesses but I am sure that someone can explain precisely.
If the coins were lathe turned for the preparation of the flan then would this not be a standard practise so the quantity of these would be immense. If it was an irregular practise would it not be easier to throw it back in the pot and start again as turning is labour intensive, low cost of slaves being a factor however I guess. Would deliberately defacing the face of the Emperor not raise a few eyebrows..........
Apparently "centration" is not quite the right term. See the link @Roman Collector put in Post #2. There is some interesting stuff in there.
I suppose it's also possible that there's some bias here. Perhaps an odd, quirky feature like this is far more jarring to us post-industrial people who are accustomed to absolute sameness and consistency in our coins than it would have been to the ancients.