Opal Details: 7x6mm Metal: 925 Sterling Silver Total Length: 18 inches (adjustable) Discover the elegance of our Natural Australian Opal Doublet Necklace in Sterling Silver (Stamped 925). This Doublet Opal Pendant features Genuine Natural Australian Opal Type 3, characterized by a gem doublet structure. The opal is a hydrated amorphous form of silica (SiO2nH2O), composed of silicon dioxide molecules arranged in closely packed planes. It is backed by Boulder Opal ironstone sourced from remote areas in Queensland, Australia. The two layers are expertly bonded with a silica-based adherent, ensuring consistent expansion and contraction. This feature prevents delamination when the opal comes in contact with water. The opal is guaranteed free of dyes and artificial color, falling under the classification of Natural Opal Type 3. All Australian Opal Cutters Jewellery and Loose Opal items come with our international warranty. For specific modifications, changes, or color preferences for your opal, please include a note during checkout. Upon request and at an additional charge, we offer the flexibility to change or upgrade your opal or modify the design of any item from our collection. Keep in mind that the item shown online may not precisely reflect the opal you receive due to the living play of colors, which can be challenging to capture accurately on camera.