Labradorite (specifically Galaxite or Micro-Labradorite)
Plagioclase Feldspar var. Labradorite · Semi-Precious Gemstone / Decorative Stone
Crystal System
Triclinic; typically found in massive or granular habits in igneous rocks rather than distinct crystals.
Mineral Group
Silicates (Tectosilicates); Feldspar group; Plagioclase series
Chemical Formula
(Ca,Na)(Al,Si)4O8 containing trace amounts of Iron and Magnesium
Formation Process
Igneous formation; it crystallizes from cooling magma in plutonic environments or volcanic flows. The characteristic labradorescence forms through subsolidus exsolution (separation) during slow cooling.
About This Crystal
Dark grey to black base color with a vitreous to pearly luster. This specimen is carved into a star shape and shows an opaque to translucent body. It features small, internal shimmering reflective zones and mottled inclusions of darker minerals.
Physical Characteristics
Color: Dark gray to black; Streak: White; Cleavage: Two directions at nearly 90 degrees; Fracture: Conchoidal to uneven; Specific Gravity: 2.68–2.72; Fluorescence: Generally inert but may show weak yellow or blue under UV.
Optical Properties
Refractive Index: 1.559–1.573; Birefringence: 0.008–0.010; Optical Phenomenon: Labradorescence (Schiller effect) caused by light interference in thin microscopic layers of different feldspars.
Hardness & Durability
Origin Region
Notable sources include Labrador (Canada), Madagascar, Finland (Spectrolite), and Norway. Forms in mafic igneous rocks like basalt and gabbro.
Hardness & Durability
Mohs Hardness: 6.0–6.5; Toughness: Brittle; Stability: Good, but sensitive to thermal shock and strong acids. Cleavage planes make it susceptible to cracking if struck hard.
Care & Maintenance
Clean with warm soapy water and a soft cloth; avoid ultrasonic or steam cleaners. Store separately from harder gemstones like quartz or sapphire to prevent scratching.
Rarity & Value
Common to Uncommon; values are determined by the intensity and color spectrum of the labradorescence (flash). Small tumbled or carved pieces are highly affordable ($5–$20).
Special Characteristics
Displays labradorescence (iridescence) and potential 'adularescence' in specific lighting. This specific dark, micro-crystalline variety is sometimes marketed as 'Galaxite' due to its resemblance to a starry night sky.
Lore & History
First discovered by missionaries in Labrador, Canada in 1770. Inuit lore claims the Northern Lights were trapped inside the rocks of the coast. Modern practitioners associate it with the Third Eye chakra, protection, and intuition.