This is an Australian solid boulder opal with hole drilled through worn on silver necklace from Queensland.
Incredible mixed of aquabluel, mint green, purple and salmon pink 100% natural.
Measuring approximately : 25 mm x 10 mm

More than 90% of the world's precious opals come from Australia.

Boulder opal are found only in the state of Queensland. 

An unique type of opal which is found attached to a host rock, ironstone. The line will always have an uneven appearance.