Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2) · Collector Mineral / Semi-Precious Gemstone
Crystal System
Monoclinic; commonly occurs in massive, scaly, or granular aggregates (micaceous habit)
Mineral Group
Silicates; Phyllosilicate (Mica group)
Chemical Formula
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
Formation Process
Igneous formation; specifically occurs in the late stages of magmatic crystallization within lithium-bearing granitic pegmatites.
About This Crystal
The specimen shows a characteristic purplish-pink to lilac hue with a pearly to vitreous luster. It appears as scaly, micaceous masses embedded within a greyish matrix. The texture is distinctly platy or granular.
Physical Characteristics
Color: Pink, lilac, or violet; Streak: White; Cleavage: Perfect basal (one direction); Fracture: Uneven; Specific Gravity: 2.8–2.9; Fluorescence: Occasionally creamy white or yellow under UV.
Optical Properties
Refractive Index: 1.525–1.587; Birefringence: 0.021–0.050; Pleochroism: Weak to moderate (colorless, pink, lilac); Biaxial negative.
Hardness & Durability
Origin Region
Notable sources include Brazil (Minas Gerais), Madagascar, Canada, and the USA (California and Maine); found in granitic pegmatites.
Hardness & Durability
Mohs Hardness: 2.5–3; very low durability. It is brittle and easily scratched; not recommended for high-wear jewelry without a protective setting.
Care & Maintenance
Clean with warm soapy water and a soft cloth only. Avoid ultrasonic cleaners, steam, and harsh chemicals. Store separately from harder stones to prevent scratching.
Rarity & Value
Common mineral but high-quality large lilac-colored scales are prized. Value is relatively low, primarily used for cabochons, carvings, or as a lithium ore.
Special Characteristics
Highly micaceous texture (scaly appearance); it is a major source of the rare alkali metal lithium and often contains trace amounts of rubidium.
Lore & History
First discovered in the 18th century and named from the Greek 'lepidos' for scale. In metaphysical traditions, it is known as a 'stone of transition' and associated with the crown and third-eye chakras for its believed calming properties due to its lithium content.