37cts Crystal Opal Specimen Rough- 7 g

Crystal opals are valued for their play-of-color phenomenon, displaying vibrant flashes of various colors depending on the angle of light. Rough crystal opal specimens, such as this 37-carat example, reveal the stone's natural internal structure before cutting and polishing. Opals form from silica deposits in low-temperature sedimentary environments, and their unique internal lattice diffracts light, creating their signature iridescence. Rough specimens are of interest both to gem cutters seeking high-quality gemstones and collectors who appreciate the raw beauty and geological formation of precious opals, particularly from well-known locations such as Australia and Ethiopia.