Celluloid sparkle bracelet, Art Deco.
So very Flapper... Very 1920's.
Usually, these are celluloid, sometimes bakelite. This one is a bit of a puzzle. It's a dark, almost black transparent color and very glossy. It does not pass the bakelite test and I've never seen this color in celluloid and it's a bit thicker than most of the applejuice celluloid that I have. It could be coated with something, making it harder to figure out.
It is obviously old, not 60's lucite, older than that and 2 1/2" on the inside diameter. Lucite is almost always bigger than that, wider and heavier and not in a sliced style.
Having speculated, let me tell you what I do know. It's a killer, Art Deco Bangle! A two row sparkle bracelet, with a double line etched and painted in the middle. Very fine workmanship. It is 3/8" wide, no chips or cracks, the paint is in great shape, no missing stones, 4 or 5 of them have darkened a bit.
This bracelet will compliment any celluloid sparkle collection you have and looks fantastic on the arm!