I thought of the makers of sulphide marbles from Germany. They often used rather crude sulphides.
I have never really looked into the marbles side of things, but of the ones I have seen (a very few in real life and some in books), the sulphide and the working was very much like those in the weight.
And yes, the Stanley Block books should provide good clues. Perhaps the website http://www.blocksite.com/
could be of help?
Another reference showing a selection of sulphide weights (as opposed to marbles) is Peter Von Brackel's Paperweights, Historicism, Art Nouveau, Art Deco, 1842 to Present
. [ I really must type up that title in Word and just copy and paste to messages :!: ] Attributions are given as (probably) Silesia / Bohemia, Thuringia, Germany, Belgium, Bohemia / Czechoslovakia and a few other choices, too.
(I had thought that for general searches on the web, I really should look for "sulfide" instead of "sulphide" as I assumed most of the hits would be in US-based pages. But for eBay listings, using eBay.com, "sulfide marble" recently gave 6 hits while "sulphide marble" produced 41. That shows how much I know about that subject