I am wondering how other collectors judge the rarity of an ancient coin. Of course, the easiest way is to check a copy of Sears works, but like any other catalogs they have mistakes and of course the books become easily dated. I collect Byzantine so no update of Sear has occurred in decades. In the artworld older works such as Rembrandt and Durer are judged by how many times pieces come to market, this of course makes sense since these were created before the concept of limited editions. This concept was done in the CLBC catalog for Byzantine coins, the authors used coin archives to track previous sales of the coins. We have no idea how many of different types of a coin were made, I am very specialized so I find how many examples that are listed in primarily Dumbarton Oakes Catalog, that gives me some insight to rarity I also rely on Archeological data on stray coin finds and hoard finds. I am curios how other collectors judge rarity, it does not matter if you collect Greek Roman or Other , I would enjoy to hear your insights.