Rock & Mineral Encyclopedia

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

Blue Calcite

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

A soft, glowing orange variety of calcite colored by iron oxides, popular as tumbled stones and known for fizzing in acid.

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

Translucent banded calcium-carbonate stone deposited in caves and springs, prized for ornamental carvings despite its softness.

A soft, fine-grained, translucent form of gypsum (or banded calcite) long prized as a carving and ornamental stone.

A banded, porous limestone deposited by mineral springs, prized as a warm-toned natural building and tile stone.

A green-and-white banded metamorphic marble whose wavy mica layers resemble the rings of a sliced onion.

An affordable multicolored banded and mossy chalcedony from India, common in tumbled stones, beads, and meditation pieces.

A vivid yellow-and-black banded stone from Indonesian volcanic vents, colored by sulfur, arsenic minerals and iron oxides, not true jasper.

A soft pale-blue calcium sulfate, the anhydrous form of gypsum, prized as a gentle, calming tumbled stone.

Tourmaline displaying chatoyancy, a moving band of light caused by parallel tube-like inclusions, when cut as a cabochon.

Beryl displaying chatoyancy, a bright moving band of light, caused by parallel tube-like inclusions when cut as a cabochon.

Pink beryl (morganite) that shows chatoyancy, a moving band of light, when cut as a cabochon, thanks to parallel tube inclusions.