Black Opal – is the family of opal which shows a  play-of-colour within or on a black body tone when viewed face-up.
Precious opal with black body color. Also used for black potch covered with thin layer of crystal opal that lets the black under layer show through.
Found mainly at Lightning Ridge in NSW and some areas in South Australia, this magnificent variety in gem quality is arguably the most valuable. Ablaze with colour, its dark appearance distinguishes it from Light Opal.
Black opal is the most rare and valuable of all opal. It is solid and generally found as a bar (or bars) of various colours in a dark body (black, blue, brown or grey). Some black opals have a complete rainbow of colours while others have deep blue-green hues.
In addition, there are also semi-black opals and black crystal opals. While a true black opal displays sharp brilliant colours on a dark background, the semi-black opal shows a background or body colour of mid-grey. In contrast, the black crystal opal is translucent with no traces of black potch on it underside. Its colours are sharp and visible beneath the surface.
Few realise that 99.9 per cent of the world's supply of this radiant gem is mined at only three pinpoints on the globeÑLightning Ridge, Mintabie and Andamooka. The majority of opal found at Mintabie and Andamooka is classified as semi-black opal.