I happen to see Miller's Encyclopedia of World Silver Marks vol. I, II. It was a disappointment. The Russian and Ukraine sectors contain a lot of incorrect information and misspellings (probably copied from Watts). Anyway, I stumbled into a name; Kapiton Sidorov. On page 763, Ukraine, is stated that he assayed in Kharkov/Kharkiv (ХАРКIB) 1845 and marked K.C. (The town's name is misspelled; Harkiv.) Anyway, I haven't seen this name mentioned before. Does anybody know something about this Russian assayer or is it picked from the sky?