Post
by blakstone » Wed Oct 31, 2012 10:06 pm
Well, the "crab" mark means it's provincial, not Parisian, so identifying the maker's mark is going to be like searching for a needle in a haystack unless you can narrow down the place of manufacture. Clean the mark well and examine it with a 10x or (even better) 20x loupe. Between the crab's lower legs is the différent: an identifying symbol unique to each assay office. These are notoriously difficult to identify, given their minuscule size and that many of them are arcane and unusual: astronomical symbols, Phonecian letters, etc. But if you can identify it, it will tell you where the piece was assayed and therefore which reference to consult.
I'll do my best to help if you can get a good clean image of the différent: not easy, but not impossible with a camera with a good macro setting.