Rock Identifier

Rock & Mineral Encyclopedia

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

Green Opal

Green Opal

A common opal colored green by nickel or chromium impurities, usually opaque and cut into cabochons and beads.

gemstone
Chocolate Opal

Chocolate Opal

Precious opal with a warm chocolate-brown body tone that makes its rainbow play-of-color glow, mainly from Ethiopia and Mexico.

gemstone

Mintabie Opal

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

gemstone
Rainbow Opal

Rainbow Opal

Precious opal that displays a broad, vivid sweep of spectral colors, flashing the full rainbow as it is tilted in the light.

gemstone
Shell Opal

Shell Opal

Fossil shells whose original material has been replaced by opal, preserving ancient marine forms in common or precious opal.

gemstone
Gold Opal

Gold Opal

A golden-toned opal ranging from translucent common opal to precious stones flashing color against a warm yellow body.

gemstone
Lavender Opal

Lavender Opal

A pastel purple variety of common opal, valued for its gentle lilac body color rather than any play-of-color.

gemstone
Jelly Opal

Jelly Opal

A translucent, gelatinous-looking opal whose transparency gives floating, glowing play-of-color a watery, jelly-like appearance.

gemstone

Madagascar Opal

Opal from Madagascar spanning colorful common opal and some precious opal, including pink, green and boulder-type material.

gemstone
Water Opal

Water Opal

A transparent, colorless opal that looks like water or jelly, sometimes flashing subtle play-of-color from within.

gemstone

Pink Opal

A soft pink common opal, most famously from Peru, valued for its gentle pastel color rather than play-of-color.

gemstone
Star Opal

Star Opal

Opal that displays a radiating, star-shaped pattern of play-of-color, a rare and prized internal structure.

gemstone

Ice Opal

A clear, glassy, near-colorless opal resembling ice, sometimes with subtle internal flashes of play-of-color.

gemstone
Australian Opal

Australian Opal

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

gemstone
White Opal

White Opal

The most common precious opal, with a pale milky body that shows softer pastel flashes of play-of-color throughout.

gemstone

Flame Opal

A glowing orange-to-red opal whose warm body color resembles flame; some stones add flashes of play-of-color.

gemstone
Blue Opal

Blue Opal

A soft blue common opal, famously from Peru, valued for its serene sky-to-teal color rather than play-of-color.

gemstone
Spencer Opal

Spencer Opal

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

gemstone
Nevada Opal

Nevada Opal

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

gemstone
Lemon Opal

Lemon Opal

A bright lemon-yellow opal, usually common opal, valued for its cheerful citrus color and translucent glow.

gemstone

Tintenbar Opal

Rare precious opal from Tintenbar in northern New South Wales, Australia, occurring in volcanic basalt rather than sedimentary rock.

gemstone

Mint Opal

A soft mint-green variety of common opal, usually opaque and colored by trace copper or nontronite inclusions rather than play-of-color.

gemstone

Girasol Opal

A transparent to milky opal that displays a soft bluish-white internal glow or sheen that seems to follow the light source.

gemstone
Harlequin Opal

Harlequin Opal

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

gemstone