Featured Black (mourning?) brooch

Hello,

I hope you are all well!
I'm writing you about a black round brooch, with a carved leaf motif and a central round floral decoration surrounded by black rhinestones. The brooch has a trombone clasp. This piece is very charming, but unfortunately I have no information about its geographic origin or its age.

The disc (4.5 cm diameter) is very lightweight and is not perfectly flat, but has some kind of very slight ondulation when looked from the side. The little black faceted stones are not all identical in size.
What kind of material could it be? Plastic/early plastic/other?
How could I understand more about its dating? My conjecture would be Victorian mourning brooch (or a later Victorian revival) but I don't know much about this period...

Thank you very much!

 

horn..?

 

Horn would make much more sense, as it would explain the kind of carving too!

 

Horn reacts under UV light so you could try that?

 

Could be Gutta Percha.

Gutta Percha is a rubber-like gum made of the resin derived from trees in Southeast Asia, mainly Malaysia. Like its synthetic cousin, vulcanite, it is brownish-black in appearance (but tended to hold its black matte color over time better) and is molded rather than carved—so, "sometimes you can detect mold lines, with the eye or a loupe," Stockhammer observes. It will give off an acrid, rubber smell when rubbed briskly.


Highly flexible yet durable, it was first used during the 1840s for jewelry. In the latter 19th century, it was employed as a less expensive substitute for jet in mourning jewelry. (taken from thesprucecrafts.com)

 

I was thinking vulcanite. It's hard rubber and turns that color brown with age. Browner than gutta percha. The trombone clasp means it was made post-1850-something.

 

With that hinge and clasp, late 19th and probably French.

 

Have you thought of jet? That’s also lightweight and easily carved.