Lepidolite Schist (Purple Mica)
Lepidolite (K(Li,Al)3(Al,Si)4O10(F,OH)2) in Mica Schist · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Monoclinic; typically exhibits a foliated, micaceous, or massive habit
Mineral Group
Silicates; Phyllosilicates (Mica Group)
Chemical Formula
K(Li,Al)3(Al,Si)4O10(F,OH)2 with trace Manganese (Mn) for color
Formation Process
Igneous (pegmatitic crystallization) or metamorphic; specifically forms in late-stage granite pegmatites via hydrothermal replacement
About This Crystal
The specimen is a purple-to-lilac foliated rock with a distinct layered/schistose texture. It is opaque to translucent on thin edges with a pearly to vitreous luster. It shows prominent parallel banding of light quartz/feldspar and dark purple mica plates.
Physical Characteristics
Color: Lilac to deep purple; Streak: White; Cleavage: Perfect basal (micaceous); Fracture: Uneven; Specific Gravity: 2.8–2.9; Fluorescence: Occasionally cream or yellow under UV.
Optical Properties
Biaxial negative; Refractive Index: 1.525–1.587; Birefringence: 0.018–0.038; no significant pleochroism in massive form
Hardness & Durability
Origin Region
Brazil (Minas Gerais), Madagascar, Canada, and USA; typically found in lithium-bearing granite pegmatites
Hardness & Durability
Mohs hardness 2.5–3.5; Very soft and brittle; poor durability for jewelry unless cabochons are stabilized; prone to splitting along cleavage planes.
Care & Maintenance
Avoid ultrasonic cleaners and steam; clean only with warm soapy water. Store away from harder gems to prevent scratching. Keep away from high heat and strong acids.
Rarity & Value
Common; Value is generally low for rough specimens, determined by color intensity and the presence of other minerals like Pink Tourmaline. Often sold as landscaping stone or lapidary rough.
Special Characteristics
High lithium content; high pearly luster on cleavage faces; often forms as a matrix for other rare pegmatite minerals.
Lore & History
Historically known as 'Lepidolite' from the Greek 'lepidos' for scale. In metaphysical practices, it is known as the 'Stone of Transition' or 'Peace Stone,' associated with the Crown Chakra and believed to aid in stress reduction due to its natural lithium content.