Sterling silver pierced post earrings by Navajo artist Ronnie Willis. They are signed on the back. The tanzanite blue stones are testing borderline glass/tanzanite, so I am going with glass. There are etching marks in the face of the stones. See close-up photos. Cannot be seen while wearing, but I examine every flaw. 

Measure 5/8" square. Weight: 8.8 grams.