Labradorite
Feldspar group, Plagioclase series, Labradorite · Semi-Precious Gemstone / Decorative Stone
Crystal System
Triclinic, typically found in massive, granular, or tabular crystal habits.
Mineral Group
Silicates (Framework silicates / Tectosilicates)
Chemical Formula
(Na,Ca)(Al,Si)4O8
Formation Process
Forms primarily in igneous rocks such as mafic igneous rocks, gabbro, basalt, and anorthosites, as well as in pegmatites through slow cooling of magma.
About This Crystal
The specimen is a carved, polished heart showing a dark greyish to greenish base with striking flashes of purple, blue, and silver chatoyancy. It has a vitreous to pearly luster and opaque to translucent transparency.
Physical Characteristics
Body color ranges from dark grey, brown, to near black; streak is white. It has perfect cleavage in two directions intersecting at roughly 87 degrees. Fracture is uneven to conchoidal. Specific gravity is around 2.68 to 2.72.
Optical Properties
Biaxial positive with a refractive index between 1.559 and 1.570. Exhibits strong labradorescence, a specialized form of adularescence caused by light interference within microscopic lamellar intergrowths.
Hardness & Durability
Origin Region
Madagascar, Finland (Spectrolite), Canada (Labrador), Australia, Mexico, and the USA.
Hardness & Durability
Mohs hardness of 6 to 6.5. Fairly good durability, but has distinct cleavage which makes it susceptible to chipping if struck sharply. Suitable for pendants, earrings, and rings with protective settings.
Care & Maintenance
Clean with warm soapy water and a soft cloth. Avoid ultrasonic cleaners, steam cleaners, and harsh chemical detergents. Store separately from harder gemstones to prevent scratching.
Rarity & Value
Common to uncommon depending on the quality of the flash and play of color. High-grade specimens with full-spectrum labradorescence (like Finnish Spectrolite) command higher values.
Special Characteristics
Labradorescence, producing brilliant iridescent flashes of peacock blue, green, gold, and purple when viewed at specific angles due to phase separation in the plagioclase feldspar.
Lore & History
Discovered in Labrador, Canada, in 1770 and named after the region. Inuit folklore suggests the Northern Lights were trapped inside the rocks. In modern metaphysical practices, it is considered a stone of transformation, enhancing intuition and protecting the aura.