Rock & Mineral Encyclopedia

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

Lherzolite

The most common type of mantle peridotite, made of olivine with both orthopyroxene and clinopyroxene, representing fertile upper-mantle rock.

A dark, highly vesicular volcanic rock full of gas bubbles, denser than pumice, common as red or black lava rock.

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

A common potassium feldspar identical in composition to orthoclase but more ordered, famous for its green gem variety amazonite.