Opals try mined in different cities international, but the majority are located in australia. Opal has relatively lowest occurrence versus a great many other gems so also big brands might be comfy to put on. In the end, it is more about personal preference and you may budget, since the man-made and you can lab-created opals are cheaper compared to the uncommon natural gem stone. Naturally, there will be something special regarding the getting a naturally occurring rainbow brick.