Hello all! I have noticed that some coins are often listed by their "Y" catalog numbers rather than their "KM" numbers on Numista. I have noticed this mostly on coins from Asian countries. For instance, this coin: https://en.numista.com/catalogue/pieces966.html This 70-111 (1981-2022) Taiwan 1 New Dollar is listed as Y-551, its catalog number referring to A Catalog of Modern World Coins by Richard S. Yeoman, and no KM number is listed. Upon looking up the coin further--such as in NGC's World Coin Lookup--I could not find any reference to its KM number, only the Y number. I have not ever read Yeoman's book, but I assume it covers all countries just like Krause and Mishler's catalog. I do not have a copy of Krause and Mishler's catalog on hand. Does anyone know why this coin does not seem to have a KM number? Does Krause and Mishler's Standard Catalog of World Coins not list this coin? Is Yeoman's catalog considered a better reference for coins of some Asian countries? Thanks, SorenCoins
Back when I was doing new issues for SCWC we continued using Y numbers for China due to our agreement with Whitman publishing who owned the rights to use the Y numbers. Don't know if they required it or it was KP's choice. The coin is listed as Y-551 under Taiwan.