Center Measures approx. 1 3/8" X 1/2" at its widest across the top, and is not marked. Neat Ring! Sorry, I do not know what the stone is. Thanks and please check out all photos and ask any and all questions prior to looking, Thanks!! Launched from my store - Powered by Highwire.com Track Page Views WithAuctiva's FREE CounterEvery buyer gets a MyStoreRewards invitation for cash back
