Yes, as stated, it is Sterling Silver. Sorry, I don't know anything about the stone. I won this ring here on Listia, have worn it and really don't have any other turquoise to go with it, so I'm passing it on.
I really know nothing of the history of the ring. It is beautiful but as I stated I really don't have any other turquoise to wear with it. I won it on Listia and I don't know much more. Sorry.