Amazonite
Microcline var. Amazonite · Semi-Precious Gemstone and Decorative Stone
Crystal System
Triclinic, typically forms prismatic crystals or massive blocks with prominent twinning
Mineral Group
Silicates (Tectosilicates, Feldspar group)
Chemical Formula
KAlSi3O8
Formation Process
Igneous and pegmatitic formation, crystallizing slowly from cooling magma rich in volatiles at high temperatures and pressures
About This Crystal
A polished, tumbled green to bluish-green gemstone with a characteristic mottled pattern of lighter streaks and white or grey albite inclusions, exhibiting a vitreous to pearly luster and translucent to opaque transparency
Physical Characteristics
Color ranges from bright turquoise-green to pale blue-green with white striations; white streak; perfect cleavage in two directions at near right angles; uneven to conchoidal fracture; specific gravity around 2.56; brittle tenacity
Optical Properties
Biaxial negative with refractive indices ranging between 1.514 and 1.530; low birefringence; weak or absent pleochroism
Hardness & Durability
Origin Region
Notable sources include Russia (Ilmen Mountains), the United States (Colorado), Madagascar, Brazil, and Namibia
Hardness & Durability
Mohs hardness of 6 to 6.5; fair toughness but vulnerable to cleavage planes; moderate durability for jewelry with protective settings
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid ultrasonic cleaners, harsh chemicals, and sudden temperature changes which can cause fracture along cleavage planes
Rarity & Value
Common to uncommon; value is determined by vivid color saturation, lack of heavy white streaks, and size; affordable price range for tumbled stones
Special Characteristics
Often displays a characteristic grid-like twinning pattern known as cross-hatch twinning and subtle schiller effects due to perthitic intergrowths of albite
Lore & History
Named after the Amazon River though no deposits are found there, historically associated with ancient Egyptian jewelry and artifacts, and traditionally used in crystal healing to promote soothing energy, truth, and balance