The 15 large beads in this necklace are coprolite, yes, fossilized dinosaur dung. The coppery beads are fire polished Czech glass, not metal so no tarnishing, they will always look like they do now. Casual enough for jeans, elegant enough for anything else. And, the coprolite beads make for a fun conversation. This necklace is 18 inches long and a 2-inch extender chain is included.