mineral

Labradorite

Labradorite, calcium-rich plagioclase feldspar; approximately (Ca,Na)(Al,Si)₄O₈

AI-generated identification · may be incorrect

Hardness 6–6.5 Mohs; gray to brown body color with strong blue-green-gold iridescence (labradorescence), usually vitreous to pearly luster. It has triclinic crystals, two good cleavage directions, and specific gravity about 2.68–2.72.

Identified August 8, 2026More mineral →

Explore Labradorite in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Forms mainly in mafic igneous rocks such as gabbro, basalt, and anorthosite as magma cools; notable deposits are Precambrian to younger. The pictured piece appears polished or tumbled, enhancing its flash.

Uses & applications

Used for cabochons, beads, carvings, ornamental stone, and collector specimens; large architectural slabs are sometimes marketed as “labradorite granite.”

Geological facts

Its color flash results from light interference between microscopic lamellae produced by exsolution within the feldspar. Spectrolite is a highly colorful Finnish variety of labradorite.

Field identification & locations

Identify it by gray translucent body material and broad moving flashes when tilted under directional light; distinguish it from moonstone by its darker body and blue-green rather than milky adularescence. Common sources include Madagascar, Finland, Canada, Norway, and Russia.