♥️ This estate boulder opal is a good sized stone. Measurements are approximately 13 mm x 11 mm by 8/9 mm depth. Using dendritics gem calculator you can estimate gem size. The stone appears as Boulder opals do, as a brown stone with some variations. But when light or flash hits, the colors which emanate are a vibrant royal blue and a vivid neon green. Really stunning. The base of the shank on the ring is set up high. 10 k gold confirmed. Total weight is 3.95 grams. Ring size is 6.5-6.75. Estate jewelry is sold in as is condition . No trades. Cheaper in a jewelry bundle.