The pattern reminded me of the waves on an ocean beach. The stone is 25mm x 15mm x 3mm thick, has a solid Ironstone back and would make a beautiful necklace pendant. The item "Solid Boulder Opal 15 carats Blue & Green #1" is in sale since Monday, July 27, 2020. This item is in the category "Jewelry & Watches\Loose Diamonds & Gemstones\Loose Gemstones\Opal\Boulder Opals". The seller is "elfaroman" and is located in Portland, Oregon. This item can be shipped to United States.