Labradorite

Physical Properties

Hardness: 6.0-6.5 on Mohs scale; Color: Dark grey to grey-green with schiller effect; Luster: Vitreous to pearly; Crystal structure: Triclinic; Cleavage: Perfect in two directions.

Formation & Geological History

Formed in mafic igneous rocks through slow cooling and crystallization of magma. Notable as an intermediate-to-calcic member of the plagioclase series. Primarily Precambrian origin.

Uses & Applications

Used widely in jewelry (cabochons), interior decoration (countertops), and as a popular ornamental collectors specimen due to its iridescent play of color.

Geological Facts

Exhibits a unique optical phenomenon called labradorescence, which is caused by light reflecting off submicroscopic layers of exsolution lamellae within the feldspar.

Field Identification & Locations

Identify by rotating under light to find the 'flash' or blue/gold labradorescence. Commonly found in Labrador (Canada), Madagascar, Finland (Spectrolite), and Norway.

Identified on: 5/19/2026

Mode: Standard