Oval Blue-Green Black Jelly Crystal Opal from Lightning Ridge

About Black Jelly Crystal Opal

Black Jelly Crystal Opal is a descriptive trade term rather than a separate mineral species. It refers to opal with a dark grey to black body tone and a translucent, sometimes glassy or jelly-like appearance. Many specimens show play-of-colour: shifting flashes of red, orange, green or blue caused by light interacting with regularly arranged silica spheres. Opal is hydrated, amorphous silica, meaning it has no crystal…