Boulder opal is a type of opal that forms within the cavities of ironstone boulders in both vertical and horizontal cracks. It is cut with the ironstone remaining on the back and is classified as solid opal. It occurs over a wide area of Western Queensland from North of Winton to south of Quilpie. It is the second most valuable Australian opal after black opal. When looked at from the side you can always tell a genuine solid boulder opal by the natural imperfect line where the opal filled the void in the boulder.Boulder opal is finished in many different shapes rather than the traditional oval of many other stones and as such is more unique and interesting. It is famous for its brightness and variety of colours with all the shades of other types of opal and can be dark or light body tone. We will then send you a combined invoice and post together in one package. We only charge what Australia post charges us and will include as many items in one package as possible. At all times to take the most true to life pictures possible. And light differently and variations may occur. We guarantee all our items to be exactly as described, genuine, natural and untreated. Please refer to measurements for actual size. The item "Australian Boulder Opal, Solid Natural, Polished Gem, Loose Stone, 30x19mm 10503" is in sale since Wednesday, November 11, 2020. This item is in the category "Jewellery & Watches\Loose Diamonds & Gemstones\Loose Gemstones\Opal\Other Opals". The seller is "boulder-opal-wholesalers-qld" and is located in The Summit. This item can be shipped worldwide.