When an occasion arises where one must appear mysterious & intriguing (and we all have these moments), there's nothing quite like the elegant blackness of jet and onyx jewels to get the point across:
Antique onyx intaglio set in yellow gold ring, featuring a miniature scene of Poseidon.
Extra-long Victorian drop earrings of carved jet with saw-tooth gold caps.
Art Deco earrings of polished onyx with platinum & diamond embellishment.
Victorian collar of carved jet beads.