Gemstone profile and identification guide
Labradorite
Labradorite is a plagioclase feldspar known for labradorescence caused by light interference in lamellar structures.
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Overview
Labradorite is a plagioclase feldspar known for labradorescence caused by light interference in lamellar structures.
Did you know? Finland material marketed as spectrolite is known for broad, vivid spectral flash colours.
Use this profile as a collector reference and educational guide for quick on-page comparison, then validate with the interactive identification system.
Identification
Name: Labradorite
Scientific classification: Silicate (Plagioclase Feldspar)
Hardness: 6.25 Mohs
Transparency: translucent
Lustre: vitreous
Crystal system: Triclinic
Primary colour: Grey
Secondary colour: Blue
Colour family: Greys
Diagnostic traits include labradorescence, plagioclase twinning features, and feldspar cleavage.
Verification Status
Status: verified-core-fields
Reference priority: GIA, Gem-A, Mindat, International Gem Society
Core identity, locality, and physical-property fields reviewed against standard gemological references.
Values are given as practical gemological ranges where appropriate.
Physical Properties
Hardness category: hard
Hardness value: 6.25 Mohs
Chemical composition: (Ca,Na)(Al,Si)4O8
Crystal system: Triclinic
Common locations: Canada (Labrador), Finland, Madagascar, Russia, Mexico
Learn more: Gem-A gemstone education resources.
Colour Variations
Grey to dark feldspar body colour with blue, green, or gold labradorescent flashes.
Optical effects: Labradorescence
Detailed Gemology
Mineral species: Labradorite (plagioclase feldspar)
Mineral group: Feldspar group
Chemical formula: (Ca,Na)(Al,Si)4O8
Mohs hardness: 6.25
Crystal system: Triclinic
Lustre: vitreous
Transparency: translucent
Streak: White
Cleavage: Perfect in two directions
Fracture: Uneven to conchoidal
Specific gravity: 2.68-2.72
Refractive index: 1.559-1.573
Optical phenomena: Labradorescence
Colour range: Grey body colour with blue, green, gold, and multicolour flashes
Common inclusions: Lamellar twinning, fracture veils, dark mineral specks
Geological environment: Mafic igneous rocks and anorthosite bodies
Principal mining regions: Canada (Labrador), Finland, Madagascar, Russia, Mexico
Important commercial sources: Commercial labradorite comes mainly from Madagascar and Mexico, with classic material from Labrador and Finland
Historical significance: Recognized as a decorative stone since the 18th century in northern Europe.
Common treatments: Generally untreated; occasional surface stabilization may occur.
Synthetic or imitation forms: Glass imitations with artificial flash effects exist.
Common look-alikes: Labradorite-look glass, moonstone, spectrolite marketed variants
Jewellery uses: Used in cabochons, carvings, beads, and decorative slabs.
Care recommendations: Moderately durable but cleavage-sensitive; avoid impact and ultrasonic cleaning.
Cross-check profile data with GIA Gem Encyclopedia and Mindat entry for Labradorite.
Formation
Crystallizes in mafic igneous rocks and anorthosites where exsolution lamellae develop optical play effects.
Origin
Commercial labradorite comes mainly from Madagascar and Mexico, with classic material from Labrador and Finland
Uses
Best for: Used in cabochons, carvings, beads, and decorative slabs.
Ideal uses: Cabochons and carvings cut to maximize directional labradorescence.
Care
Moderately durable but cleavage-sensitive; avoid impact and ultrasonic cleaning.
Need another candidate? Use advanced gemstone search or return to the identification guide.
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Labradorite FAQ
How can I identify Labradorite?
Compare hardness (6.25 Mohs), crystal system (Triclinic), colour profile, and lustre (vitreous) with your sample. Then cross-check related gemstones listed above.
What colour range does Labradorite appear in?
Grey to dark feldspar body colour with blue, green, or gold labradorescent flashes.
Where is Labradorite commonly used?
Cabochons and carvings cut to maximize directional labradorescence.. For maintenance, follow the care guidance in this profile.
Scientific References
GIA: general gemstone identity (reviewed) - Batch 01 factual verification pass.
Gem-A: gemological terminology and testing references (reviewed) - Batch 01 factual verification pass.
Mindat: mineral species and principal localities (reviewed) - Batch 01 factual verification pass.
International Gem Society: gem trade context and treatment overview (reviewed) - Batch 01 factual verification pass.