Rock & Mineral Encyclopedia

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

Satin Opal

Opal showing a smooth, silky satin-like sheen across its surface, valued for a gentle, refined luster.

An opaque, porcelain-white common opal prized for its milky, pearl-like appearance and high porosity, often carved or beaded.

Opal with a soft, velvety surface sheen rather than sharp play-of-color, prized for its gentle glow.

Fossil material whose original substance has been replaced by opal, preserving ancient shapes in common or play-of-color opal.

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

An opal with a deep red body color, often a variety of Mexican fire opal, prized for its warm, glowing intensity.

A translucent red opal, closely related to Mexican fire opal, glowing with a warm cherry-red body color often free of play-of-color.

A patterned common opal with mottled, leopard-like spots and blotches, prized as an ornamental and cabochon stone.

A rare opal pseudomorph from White Cliffs, Australia, formed as opal replaced clustered crystals into a pineapple-like shape.

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

A clear, glassy, botryoidal common opal famous for its intense green fluorescence under UV light, caused by trace uranium.

A soft pink common opal from the Peruvian Andes, prized for its opaque rosy color rather than play-of-color.

A translucent common opal from the Andes prized for its serene blue to blue-green color, usually cut into cabochons and beads.

An opal cut to show chatoyancy, a sharp moving band of light like a cat's eye, usually in honey, green or yellow common opal.