My view on the matter depends who is the professional. I do not see collectors as having the responsibility to point out errors to dealers BUT if a dealer asks my opinion on a coin BEFORE I have put it in my buy pile, I should reply to him honestly. In the mid 1990's I taught more than one dealer how to tell Alexandria mint denarii. Enough listened and it ended up costing me money. I frequently point out errors to dealers but usually on coins in which I have no interest. Some dealers change the listing or delist the item. Some do not. Some say thanks. On the other hand, anyone who is offered coins for sale to a dealer AND asks for ID, deserves to be told what the coins are along with the offer. Many people do not care about the ID but only how much they can get for grandpa's coins. If an error is seen in an auction after it has received even one bid, I do not believe that a seller should correct that error but should notify the bidder that there was an error and offer to cancel the bid. Fakes discovered late should be delisted. A story: I was in a brick and mortar shop in a town I was visiting where I was shown quite a few coins the dealer said were brought in by a widow. He went on to explain that she did not know the good ones from the bad and that he got a really good deal on them. He bragged about how much he knew about ancients. The more he said about the matter, the less guilty I felt about not telling him the Claudius II in his case was a Marius. He paid the widow for a Claudius and sold it to me as a Claudius. I'll never again be in that town but if I were, I would not return. Moral: If you are in the business of fleecing widows, don't brag about it.
furryfrog, I'm interested in Byzantine coinage but know very little about them. I'm familiar with Byzantine history (they were my ancestors) and liturgical chant, but know next to nothing about the coinage. I can read Greek and Latin, but I'd like to know what books you or others could recommend to learn more about the coinage. Thanks. BTW might your coin be an overstrike of Romanus II and not Romanus I, considering Nicephorus II (Phocas) immediately succeeded Romanus II? I don't know. Great coins BTW.
I wish I could recommend books. But alas, I don't have any. I spend a lot of time looking on CT, vcoins, and ebay at various emperors and comparing/contrasting them. There are a couple of good links though that got me started and I refer back to . Both are from CT members who know more than I could ever hope to know. @dougsmit - https://www.forumancientcoins.com/dougsmith/ @Valentinian - http://augustuscoins.com/ed/
https://www.amazon.com/Byzantine-co...ords=whitting+byzantine&qid=1597790731&sr=8-1 I recommend the above book which is not appreciated by many because it is NOT a catalog and will not identify your coins providing a catalog number. It can, however, teach you a lot about the coins. The additional suggestions on the Amazon page is the Grierson book which is now about 4x the price. It is a nice book but for the money, I like Whitting.
Yeah, that one's good, but far from comprehensive. What you probably want (and Nope, I don't have it) is Sear, Byzantine Coins. And, Oh, No, I'm about to go trawling for it online. Sorry for any ensuing competition.
Yeah, I gave up on local libraries, just starting with public ones (...God bless them, every one), for anything numismatic or historical, a long time ago. Whitting is good, but until you (or I) get a copy of Sear, the most reliable thing I know of is still the Wildwinds site. http://www.wildwinds.com/coins/
Nice overstrike. It's great when the two types are easily identifiable. (I was just looking at one yesterday that has 3 easily identifiable types!) Here's my snazzy non-overstruck Nic II, it's one of my favourite Byzantine portraits:
Very cool (alt. That's some Stuff), Sev.Alex. (...Imp.Aug.; sorry). Has a visual effect not unlike the examples of Justinian, which evoke the mosaics in Ravenna.
One of the great things about the internet is that Dumbarton Oaks has free downloadable copies of both the Grierson book and their entire five volume set of the coins in their collection on their website.
Its not my favorite book but you can find the Whitting book cheaper than Amazon. Watch the shipping part though. https://www.abebooks.com/servlet/Se...ults&kn=byzantine+coins&an=whitting&tn=&isbn=
I tried that once, and my (antiquated) machine wouldn't cooperate with the file sizes. If your machine isn't a piece of junk, it might work!