Rock & Mineral Encyclopedia

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

Honduran Opal

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

Australia's classic light-bodied precious opal from Coober Pedy, famed for milky white stones flashing pastel rainbow play-of-color.

A transparent yellow to golden gem variety of labradorite feldspar, usually faceted to show its clear, warm color.

The gem variety of corundum in every color except red, most prized in velvety blue and exceptionally hard and durable.

The blue variety of tourmaline, a relatively rare and prized color ranging from teal and greenish blue to deep indigo.

A soft, pastel minty-green tourmaline prized for its fresh, light color, a delicate variety of green elbaite.

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

The delicate pink-to-lilac variety of spodumene, a lithium silicate prized for soft color and strong pleochroism but tricky perfect cleavage.

A rich brown variety of andradite (or grossular-andradite) garnet, marketed for its warm chocolate color and notable brilliance.

The rare colorless variety of grossular garnet, a near-flawless transparent gem free of the iron and chromium that color most garnets.

A rare sky-blue variety of pectolite found only in the Dominican Republic, prized for its sea-like color and white volcanic patterning.

The red to raspberry-pink variety of tourmaline, prized for its vivid ruby-like color that holds under both daylight and artificial light.

An exceptionally hard beryllium aluminum oxide prized for golden hues, sharp cat's-eye effect, and the rare color-change alexandrite variety.

The blue color variety of beryl, ranging from pale sky tones to rich sea-blue, best known in its finest grades as aquamarine.