Rock & Mineral Encyclopedia

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

Labradorite

A plagioclase feldspar famous for labradorescence, a dramatic flash of iridescent blue, green, and gold across a dark gray stone.

A soft, soothing powder-blue variety of calcite, a common calcium carbonate mineral often sold as gentle tumbled stones.

Aquamarine crystals still attached to their natural host rock, prized as mineral specimens showing beryl in its original pocket setting.

A dark gray-to-black feldspar variety of moonstone that shows blue and white adularescent flash against a smoky body.

Natural emerald crystals still embedded in their host rock, prized as mineral specimens that show how the gem grew in place.

A feldspar, better known as sunstone, that sparkles with metallic glints from tiny mineral platelets, an effect called aventurescence.

A soft mint-to-apple-green variety of calcite, a common calcium carbonate mineral popular as soothing tumbled stones.

A striking lead chromate mineral prized for its brilliant orange-red prismatic crystals, with the finest specimens from Tasmania.

Quartz colored blue by inclusions of the mineral dumortierite, giving a denim-like blue ornamental stone harder than dumortierite alone.

The blue-grey relative of tiger's eye, a chatoyant quartz showing a shifting band of light like a bird of prey's eye.