Blue-Green Australian Crystal Opal from Coober Pedy, Freeform

About Australian Crystal Opal

Australian crystal opal is natural opal whose body is transparent to translucent, allowing light to enter the stone. Its base may be colourless, white, grey, brown or dark, while its play-of-colour can show green, blue, yellow, orange and red flashes as the stone moves. The effect is caused by the diffraction of light through regularly arranged silica spheres. Opal is a hydrated, non-crystalline form of silica rather than a…