The hamsa is a symbol that represents the hand of God/protection, and is typically worn in the Middle East by both Jews and Muslims. Though as today the local is also global, it is a not uncommon jewellery motif worldwide.

This pendant by Jewels by Durrani has a gold plated sterling silver chain, though no detail is given about the material of the hamsa itself. It looks like reconstituted opal, but may be … anything opal-like.

This sells for USD$65.