Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

Rock Type: mineral

Labradorite

Physical Properties

Hardness: 6-6.5 (Mohs), Color: Grey, black, or blue-green with iridescent labradorescence, Luster: Vitreous to pearly, Crystal structure: Triclinic, Cleavage: Perfect in two directions.

Formation & Geological History

Formed in mafic igneous rocks such as basalt and gabbro through the slow cooling of magma. Often found in anorthosite complexes. Most specimens date from the Proterozoic or Archean eons.

Uses & Applications

Primarily used in jewelry, as ornamental stones, in countertops, and as a popular metaphysical or collector's specimen.

Geological Facts

Labradorite displays a unique optical effect known as 'labradorescence,' which is caused by light diffracting within submicroscopic layers of the crystal. It was first discovered in Labrador, Canada, in 1770.

Field Identification & Locations

Identify in the field by looking for flashes of iridescent colors (blue, gold, green) when tilted in light against a dark background. Commonly found in Newfoundland (Canada), Madagascar, Norway, and Russia.

Identified on: 5/1/2026

Mode: Standard