
Onyx
$5
Onyx is an opaque banded variety of chalcedony mineral, commonly black or white, sold as tumbled stones, polished pieces, or small crystals in the fossils and minerals market.
Estimated value as of 2026 · Source: Average from tumbled/polished onyx stones on Etsy, GemSelect, and crystal retail…
Fun Fact
Onyx was historically used in ancient cameos and intaglios because its layered colors allowed skilled artisans to carve contrasting images.
Price History
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