Rock & Mineral Encyclopedia

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

Fireworks Obsidian

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

A white, porous borate mineral webbed with gray-black veins, widely dyed to imitate turquoise and other stones.

A rare agate that forms naturally with flat polygonal faces and angular geometric shapes rather than the usual rounded nodule.

A chalcedony agate with red, orange, and yellow plume or banding patterns that rise like dancing flames within the stone.

A natural volcanic glass with rich brown and black mahogany-like swirls created by iron oxide inclusions.

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

A lustrous black titanium-rich garnet of the andradite series, found in alkaline igneous rocks like nepheline syenite and ijolite.

Black volcanic glass that flashes flame-like bands of iridescent color when light strikes aligned nanoscale inclusions.

A pale jasper threaded with black, fern-like mineral dendrites that mimic plants, trees, and frost despite being inorganic.

Black volcanic glass laced with delicate web-like veins of contrasting color, formed by flow banding and fine crystallization.

Fine acicular (needle-like) tourmaline crystals, often black schorl, frequently seen as slender inclusions within clear quartz.