Bold 800 Silver Cuff Bracelet - Tia/Jia/Gia

[natNYC]

I can't quite make this out, looks like it might be TIA, JIA, or TIG?
Marked on clasp, on opposite side, marked "800"
Large purple stone
thin, flexible metal with unique "belt style" clasp closure.

Any ID help would be most appreciated!

You can click on the image for a close up.

[tatsnbikes]

Not native American. And older modernist piece.