Discover why we cut Yowah nut opals in half — the only way to reveal their hidden colour. Learn the real statistics behind these ultra-rare opal formations, why there’s no X-ray that can see inside, and the mystery of how opal forms inside solid ironstone. From our record $1.2 million Discovery Channel haul to custom-made opal jewellery, this is your ultimate guide to Australia’s rarest opal.