Hello
Don’t forget you’ve buy them maybe in Canada too?
A part of Canada is French oriented. The maybe Canadian producer made his own attempt in interpretation of French marks for «Plated». Look:
http://www.925-1000.com/silverplate_menu.html
Well you could get there an appearance of plated mark’s — but couldn’t find there actually «”LB” in a diamond» «”LB” in a diamond» resists actually to be not known yet in «925-1000».
But you were misled by phantasm to mix French MM for real silver alloy to be the same for «Plated»? It’s absolutely sure that’s never «Leon Baujois» nor «Lucien Boulard»!
As you’ve already mentioned its «E.P. ZINC» = Electro plated on zinc = zinc is one of the inexpensive basic materials for this kind of cast production process. It’s used only for mass production articles. But it’s never a zinc/silver alloy! «806» isn’t a signification of an alloy per mil but in this case maybe model number only.
For finish there were used a very thin layer of electro plated silver only; you could see now the basic material of cast zinc on edges.
Good luck in yours noviciate!
Kind regards silverport