Opal

Opal

Romans believed opal to be the most precious gemstone of all and it’s not difficult to understand why. After all, it does have a kaleidoscopic aesthetic and provides many of the colors of different gemstones. While diamonds are typically the most valuable stone, there are cases where opal has sold for more on the market. There are two key classes of opal. These are precious and common. While precious opal does display iridescence, the common form of opal does not have this quality. The commonality of opal is typically determined by the shade. Black opal is deemed to be the rarest. In contrast, grey, green and white varieties are common.