The name 'Common Opal' was chosen because this non-crystalline solid is very common and can be found in many places around the world.
Common Opal has the same chemical composition as 'Precious Opal'. The main difference is that it doesn't exhibit 'play of colour'.
Most of the world's opals are Common Opal, yet it's not that well known.
The most common colour is pink, but it can be found in many other colours. The finest grade pink opal comes from Peru.
Pink opal from Western Australia is a type of mookaite. The deposit where the stone is found is just one kilometre from where mookaite is mined.
Mookaite and pink opal are mined by the same company.
Onyx
