Labradorite
Labradorite (Plagioclase Feldspar Series: (Ca,Na)(Al,Si)4O8)
Rock Type: mineral

Physical Properties
Hardness: 6-6.5 on Mohs scale; Color: Gray to black with labradorescence (blue, green, gold flashes); Luster: Vitreous to pearly; Crystal structure: Triclinic; Cleavage: Two directions at nearly 90 degrees; Specific gravity: 2.68-2.72.
Formation & Geological History
Formed in mafic igneous rocks such as basalt or gabbro through the slow cooling of magma. Some of the most famous deposits are found in anorthosite massifs. Distinctive play of color is caused by lamellar intergrowths resulting from exsolution during cooling.
Uses & Applications
Primarily used as a gemstone in jewelry, ornamental carvings, and high-end architectural materials such as countertops and tiles. It is also a popular specimen for mineral collectors.
Geological Facts
The optical effect 'labradorescence' is named after this mineral. It was first discovered in Labrador, Canada, in 1770. It is often called 'the stone of magic' in metaphysical circles because of its sudden color shifts.
Field Identification & Locations
Identify in the field by looking for 'schiller' or iridescent flashes of color when the stone is rotated under a light source. Commonly found in Canada (Labrador), Madagascar, Finland (where it is called Spectrolite), and Russia.
Identified on: 4/14/2026
Mode: Standard