Labradorite (Schiller Spar)

Physical Properties

Hardness: 6-6.5; Color: Grey to smoke-black; Luster: Vitreous to pearly; Crystal structure: Triclinic; Cleavage: Perfect in two directions; Specific gravity: 2.68-2.72

Formation & Geological History

Formed in mafic igneous rocks like basalt and gabbro. It crystallizes from cooling magma and exhibits an internal lamellar structure that causes light interference (labradorescence).

Uses & Applications

Used primarily in jewelry (cabochons), as an ornamental stone for countertops and architectural cladding, and popular among gemstone collectors.

Geological Facts

Named after the Labrador peninsula in Canada where it was discovered in 1770. The vibrant play of color it displays is caused by light reflecting off microscopic layers of different mineral compositions.

Field Identification & Locations

Identify in the field by its distinctive 'flash' of blue, green, or gold colors when tilted in light. Found commonly in Canada, Madagascar, Norway, and Russia.

Identified on: 5/11/2026

Mode: Standard