New old store stock sterling silver ring with a large bright blue turquoise stone that has rusty brown matrix. The stone is huge measuring 32.4mm by 20mm. Size 8 Ring face is 1 3/8” long. It has a NA style hallmark of a tortoise, but I have doubts that this is actually NA. Weight: 17.2 grams. I did acid test it and it is sterling silver. Nice strong shank.?