Rock & Mineral Encyclopedia

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

Granodiorite

A common coarse-grained intrusive rock like granite but richer in plagioclase than potassium feldspar.

A coarse-grained mafic plutonic rock similar to gabbro but with orthopyroxene as the dominant pyroxene instead of clinopyroxene.

A granite-like rock containing orthopyroxene, formed at high temperatures and pressures and often classed with the granulites.

A pale rock made almost entirely of the sodium feldspar albite, formed by sodic magmatism or sodium metasomatism.

An altered granite mottled pink and green from feldspar and epidote, popular as a tough, colorful ornamental rock.

A pegmatite rock of feldspar intergrown with wedge-shaped quartz that resembles ancient runic or Hebrew writing.

An altered granite of pink feldspar, green epidote and quartz, mottled pink-and-green and popular as a tumbled and carving stone.

Wolframite is the historic principal ore of tungsten, a heavy black tungstate forming bladed crystals in granite veins.

The most abundant mineral group in Earth's crust, feldspars are aluminosilicates that form much of granite and many igneous rocks.

A fine-grained, silica-rich volcanic rock that is the extrusive equivalent of granite, often pale, banded, or flow-textured.