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.

Cherry Obsidian

A vivid cherry-red glass sold as obsidian; the bright transparent red color is manufactured, as natural obsidian only shows dull red-brown mahogany tones.

igneous
Pitchstone

Pitchstone

A dull, resinous volcanic glass similar to obsidian but with higher water content and a waxy pitch-like luster.

igneous

Lilac Obsidian

A soft pale-purple glass sold as obsidian; uniform lilac material is essentially always manufactured glass rather than natural volcanic obsidian.

igneous

Pastel Obsidian

Soft pastel-colored glass sold as obsidian; multicolor pastel material is manufactured art glass rather than natural volcanic obsidian.

igneous
Red Obsidian

Red Obsidian

Volcanic glass tinted red by fine iron-oxide inclusions, often blended with black to form mahogany-patterned obsidian.

crystal

Watermelon Obsidian

A pink-and-green bicolor glass sold as obsidian; the watermelon coloring is manufactured and does not occur in natural volcanic glass.

igneous
Fire Obsidian

Fire Obsidian

A rare obsidian showing brilliant fiery iridescence caused by thin nanolayers of magnetite crystals diffracting light within the glass.

crystal
Silver Sheen Obsidian

Silver Sheen Obsidian

Black volcanic glass displaying a silvery shimmer from light reflecting off aligned microscopic gas bubbles trapped in the obsidian.

crystal
Green Obsidian

Green Obsidian

Green-tinted volcanic glass; some is naturally colored by trace iron, but vivid emerald-green pieces are usually manufactured glass.

crystal

Royal Blue Obsidian

A deep royal-blue glass sold as obsidian; the rich blue body color is manufactured, unlike natural blue-sheen obsidian whose blue is only a surface effect.

igneous

Emerald Green Obsidian

A bright emerald-green glass sold as obsidian; saturated transparent green is manufactured, while rare natural green obsidian is only faintly tinted.

igneous

Velvet Obsidian

A black volcanic glass with a soft, velvety internal sheen caused by aligned microscopic inclusions catching the light.

igneous

Calico Obsidian

A mottled, multicolored obsidian blending black, brown, grey, and tan patches like a calico cat's patchwork coat.

igneous

Fireworks Obsidian

Black volcanic glass dotted with radiating spherulite bursts that look like exploding fireworks frozen in the stone.

igneous
Rainbow Obsidian

Rainbow Obsidian

A black volcanic glass that reveals concentric rainbow bands of color when cut and polished against the light.

igneous

Cosmic Obsidian

A trade name for sheen obsidian whose swirling, patchy iridescence resembles galaxies and nebulae against deep black glass.

igneous

Cloudy Obsidian

Obsidian with a hazy, cloud-like translucency caused by uneven distribution of tiny bubbles or incipient crystallites in the glass.

igneous

Blue Obsidian

Blue-colored volcanic glass; genuine natural blue obsidian is very rare, while much blue obsidian on the market is manufactured glass.

crystal

Peanut Obsidian

Black volcanic glass studded with oval, peanut-shaped grey-white spherulites of radiating crystals frozen in the glass.

igneous
Apache Tears

Apache Tears

Rounded nodules of translucent obsidian, named after a Native American legend, that glow smoky brown when held to light.

igneous
Banded Obsidian

Banded Obsidian

Volcanic glass marked by parallel or swirling bands of differing color that record the flow layering of cooling lava.

igneous

Spiderweb Obsidian

Black volcanic glass crossed by a fine network of grey or brown veins that resemble a spider's web.

igneous

Orange Obsidian

Obsidian colored orange by iron oxide inclusions; vivid uniform orange material is frequently manufactured glass rather than volcanic.

igneous

Stripe Obsidian

Obsidian crossed by parallel flow bands of differing color, formed as layers of lava with slightly different compositions froze into glass.

igneous