Rock & Mineral Encyclopedia

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

Aragonite

A calcium carbonate mineral and polymorph of calcite, aragonite forms distinctive needle clusters, sea shells, and pearls.

An opaque blue variety of chalcedony jasper, less common than red or green forms, colored by mineral inclusions.

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

Tourmaline in blue tones, encompassing iron-colored indicolite and the rare neon copper-bearing Paraiba, among the scarcer tourmaline colors.

A blue calcium phosphate mineral with vivid color and middling hardness, the same mineral family that forms bones and teeth.

A rounded sedimentary nodule cracked internally and filled with veins of yellow calcite, prized for its striking dragon-skin patterning.

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

A rare, prized Oregon picture jasper known for blue-green orbs and scenic patterns, often called the king of jaspers.

The blue-green gem variety of microcline feldspar, often mottled with white, prized as an affordable ornamental stone.

A deep blue copper carbonate mineral that forms in oxidized copper deposits, often alongside green malachite.

Smithsonite is a zinc carbonate ore famous for glassy botryoidal crusts in blue-green, pink, and yellow hues.

A sought-after elbaite tourmaline in teal hues that blend blue and green, prized for its ocean-like color.

A vivid blue-green hydrated copper silicate, soft on its own but prized as a gem when hardened by intergrown quartz or chalcedony.

A precious opal showing dominant peacock-like blue, green and teal play-of-color, often on Ethiopian material.