Queensland, Australia Boulder Opal Natural Untreated

Weight: 775 carats / 155 grams
*Product photo is of the actual item you will receive when ordered.
Boulder Opals are known for their wood like appearance and opal veins that give it an attractive combination and unique characteristics.  Natural Boulder Opal rocks can be used for display or by woodworkers for inlay, lapidary work or tumble polishing.  Boulder Opals are considered extremely rare because it is only found in Australia and nowhere else in the world. Boulder Opal can be categorized as a rare stone but it is more readily obtainable as compared to its cousin, black opal.  Formed in areas of Ironstone, Boulder Opals are created when the host rock (Ironstone) forms with/as part of the opal when the gem is formed in cracks/voids within the host rock. The resulting opal is often a thin vein laid on (natural) Ironstone.  Because boulder opal veins are thin in the Ironstone boulders, the host Ironstone is usually left on the back of the stone.  Natural opals are usually described as light, dark/black, boulder, and matrix. When it is transparent or very translucent, and the color clarity is sharp, it is often referred to as crystal opal.