Labradorite
(Ca,Na)(Al,Si)₄O₈
Quick Facts
About Labradorite
Labradorite is a feldspar mineral most famous for its spectacular display of iridescent colors, known as labradorescence. This 'play of color' typically features electric blues, greens, golds, and violets. It was first discovered in Labrador, Canada, from which it takes its name. Some rare varieties from Finland show almost the entire spectrum and are called 'Spectrolite'.
Formation & Geology
Labradorite forms in mafic igneous rocks, such as basalt and gabbro. The labradorescence is not caused by surface colors but by light reflecting off microscopic, twin-layered structures within the mineral. When light enters the crystal, it bounces off these layers, and the interference of the reflected light creates the shimmering colors.
Physical Characteristics
Like other feldspars, labradorite has a hardness of 6 to 6.5 and two directions of perfect cleavage. It belongs to the plagioclase series. The base color is usually a dark gray or greenish-gray, which provides a dramatic contrast for its luminous internal flashes.
Historical Significance
In Inuit legend, the Northern Lights (Aurora Borealis) were once trapped in the rocks along the coast of Labrador until an Inuit warrior struck them with his spear, releasing the lights into the sky but leaving some behind in the stones. Since its discovery in 1770, it has been a favorite for jewelry and architecture.
Colors & Varieties
Gray, green, blue, yellow (with play of color)
Key Properties
- Labradorescence (iridescence)
- Plagioclase feldspar group
- Triclinic crystal structure
- Perfect cleavage
- Vitreous luster
- Often shows twinning
Uses & Applications
- Gemstones and jewelry
- Decorative architecture (countertops)
- Ornamental carvings
- Healing crystals (transformation)
- Collector specimens
Where to Find
- Canada (Labrador) - original source
- Madagascar - major modern source
- Finland (Spectrolite)
- Norway
- Russia
- United States (Oregon)
- Mexico