These are silver metal with a genuine Swarovski 1028 xillion chaton rhinestone set in them. They come with the backs and can be set with The Crystal Applicator Tool or a Crystal Rivet Setter 8100-00 and Poundo Board #3461. See instructions under our faq "How do I set Rhinestone Rivets?". The measurement from the back of the shank to the front of the stone is 10 mm long. The length of the shank by itself is 5 mm long. The diameter of the shank is 2.6 mm wide. The diameter of the top of the rivet is 09 mm wide.