Worth some money. Opal is one of the rarest and most precious emeralds. Only Sri Lanka is produced in the world, and the price is quite expensive. 10 carat or more is hard to see in domestic shopping malls, so it was valuable in China ten years ago. Opal, a golden emerald with cat's eye effect, is also called "cat's eye", "cat's eye", "cat essence" and oriental cat's eye. It is a rare and precious variety in jewelry, also called Alexander opal, which has discoloration and cat's eye phenomenon.