Labradorite (with Chalcedony and Glass)
Plagioclase Feldspar var. Labradorite and Quartz var. Chalcedony · Semi-Precious Gemstone / Decorative Jewelry
Crystal System
Triclinic (Labradorite) and Trigonal/Monoclinic (Chalcedony); mostly used as polished beads.
Mineral Group
Silicates (Tectosilicates subclass, Plagioclase Feldspar group)
Chemical Formula
(Ca, Na)(Al, Si)4O8 (Labradorite); SiO2 (Chalcedony)
Formation Process
Igneous: crystallization from cooling magma where sodium and calcium molecules separate into thin layers.
About This Crystal
Features a mix of blue-grey labradorite beads with labradorescence (schiller effect), translucent grey-purple chalcedony, and faceted blue-coated glass crystals.
Physical Characteristics
Grey body color with blue flash, white streak, vitreous to pearly luster, translucent to opaque transparency, 2.68-2.72 specific gravity.
Optical Properties
Labradorescence (interference of light in thin lamellar twinning), refractive index 1.56-1.57, biaxial (+).
Hardness & Durability
Origin Region
Madagascar, Canada (Labrador), Finland, and Russia; typically found in mafic igneous rocks.
Hardness & Durability
6.0 to 6.5 on Mohs scale (Labradorite); brittle toughness; susceptible to pressure and scratching.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid ultrasonic cleaners, steam, and harsh chemicals.
Rarity & Value
Common; value determined by the intensity and spectrum of the color flash (labradorescence).
Special Characteristics
Labradorescence (Schiller effect) displaying metallic blues and greens; some beads show artificial metallic coatings (flashed glass).
Lore & History
First discovered in Labrador, Canada in 1770; Inuit legend claims the Northern Lights were trapped inside the stones.