Albite
Albite var. Cleavelandite · Mineral Specimen and Collector Mineral
Crystal System
Triclinic; typically forms tabular, platy aggregates, and lamellar masses
Mineral Group
Silicates, specifically Tectosilicates (Feldspar group, Plagioclase solid-solution series)
Chemical Formula
NaAlSi3O8
Formation Process
Igneous and pegmatitic crystallization, typically forming in the late stages of granitic magma cooling
About This Crystal
The specimen exhibits a dense, interlocking aggregate of white to greyish-white, platy crystals with a pearly to vitreous luster and translucent to opaque transparency
Physical Characteristics
Color is white to grey; streak is white; perfect cleavage in two directions at approximately 86-94 degrees; uneven to conchoidal fracture; specific gravity around 2.62; brittle tenacity
Optical Properties
Biaxial positive with refractive indices around 1.525-1.542; exhibits characteristic polysynthetic twinning visible as striations on cleavage faces
Hardness & Durability
Origin Region
Found globally in granite pegmatites, notably in Brazil, Madagascar, Pakistan, and the United States (Maine)
Hardness & Durability
Mohs hardness of 6 to 6.5; moderate to good durability, but has distinct cleavage making it susceptible to breakage under sharp impacts
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid harsh acids, particularly hydrofluoric acid, and ultrasonic cleaners due to cleavage planes
Rarity & Value
Common as a rock-forming mineral, but distinct crystallized specimens and attractive platy aggregates are moderately valued by collectors
Special Characteristics
Often displays polysynthetic twin striations and can occur as cleavelandite variety forming delicate, book-like lamellar plates
Lore & History
Associated with mental clarity, emotional balance, and supporting transitions; in crystal healing it is linked to the third eye and crown chakras