Labradorite (Larvikite variety)

Physical Properties

Hardness: 6-6.5 (Mohs scale), Color: Dark grey to black with blue/silver schiller (labradorescence), Luster: Vitreous to pearly, Crystal Structure: Triclinic, Cleavage: Two directions at nearly 90 degrees, Specific Gravity: 2.68-2.72

Formation & Geological History

Formed from the slow cooling of magma deep within the crust, often in anorthosite or gabbro intrusive rocks. This specific dark variety is characteristic of the Larvik Plutonic Complex in Norway, dating back to the Permian period (approx. 290 million years ago).

Uses & Applications

Commonly used in architectural cladding, high-end countertops, jewelry, and as polished spheres or palm stones for mineral collectors and metaphysical practitioners.

Geological Facts

The optical effect 'labradorescence' is caused by light reflecting off internal submicroscopic planes of exsolution lamellae. The dark Norwegian variety is often called 'Black Moonstone' or 'Blue Pearl Granite' in the trade, though it is geologically an igneous monzonite.

Field Identification & Locations

Identify by rotating the stone under a light source to find the characteristic 'flash' of blue or silver. It is found predominantly in Labrador (Canada), Madagascar, and the Larvik region of Norway.

Identified on: 4/25/2026

Mode: Standard