This measures approx. 5/8" X 3/8" at its widest, not including the loop, and dates from the 1960's, and is not marked on the back, and, please see all photos and please ask any and all questions prior to looking. Stone test as Red Spinel! This is old store stock that never sold! Thanks for looking! Launched from my store - Powered by Highwire.com Track Page Views WithAuctiva's FREE CounterEvery buyer gets a MyStoreRewards invitation for cash backPlease email us for details on this item! Unfortunately, we have thousands of items, and no easy way to handle the situation involving HTML hidden wording. We apologize to our customers.