Natural Ethiopian Black Opal Opal size is about 16mm The ring Weight about 2.8g Inner circumference is about 56mm Inside of the ring is engraved with S925 Please read carefully before placing the bids: 1. The winning bidder will receive the exact vintage piece shown in the photos. 2. Items marked as vintage are genuine vintage jewelry or antiques from my personal collection. 3. Only the jewelry shown in the listing is included in the auction. Jewelry boxes and other props are not part of the sale unless otherwise specified. Check my other listings!