Rock & Mineral Encyclopedia

Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.

Black Opal

The rarest and most valuable opal, with a dark body tone that makes its flashing rainbow play-of-color blaze brilliantly.

A hydrated silica gemstone famous for its shimmering play-of-color, ranging from white and black opal to fiery orange fire opal.

Precious opal from Spencer, Idaho, occurring in thin colorful seams that are typically cut into triplets.

Precious opal from Honduras occurring in a dark volcanic matrix, where bright flecks of color flash against a natural black basalt background.

Opal with a dark grey body tone sitting between black and light opal, giving play-of-color rich contrast at an accessible price.

The rarest and most coveted opal play-of-color pattern, showing large, evenly spaced, angular mosaic patches of color.

Precious opal from the Mintabie field in South Australia, known for hard, bright crystal opal and some dark-bodied stones.

Opal mined in Nevada, famous for fiery black precious opal and opalized wood from the Virgin Valley district.

Opal from Australia, the world's leading source of precious opal, ranging from white and crystal to prized black and boulder types.

Opal from Lightning Ridge, Australia, the world's premier source of black opal with brilliant color on a dark body.

Nevada's famous precious opal, including vivid black opal and opalized wood, renowned for brilliance but a notable tendency to craze.