Hello. I have a Mexican poison ring with the 1960s/70s Eagle mark and #111. There are conjoined HF letters and then number 5. Also marked STERLING925 and MEXICO in an oval around HF 5.
In Australia I don't have access to "The Little Book of Mexican Silver Trade and Hallmarks". If someone does can they please give me a quick rundown on this maker.
Cheers Chris

