Amazonite
Microcline var. Amazonite · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Triclinic; typically occurs in blocky, prismatic crystals or massive forms, often exhibiting Carlsbad twinning.
Mineral Group
Silicates (Tectosilicates); Potassium Feldspar group
Chemical Formula
K(AlSi3O8) with trace Lead (Pb) and water (H2O) causing the blue-green color
Formation Process
Igneous/Pegmatitic; crystallizes from slow-cooling magma in late-stage granitic pegmatites or occasionally in hydrothermal veins.
About This Crystal
A pale to vibrant blue-green color with a waxy to vitreous luster. This specimen is opaque to translucent and exhibits a characteristic 'perthitic' texture consisting of fine white streaks or mottling caused by exsolution of albite.
Physical Characteristics
Color: Blue-green/Turquoise; Streak: White; Cleavage: Two perfect planes at nearly 90 degrees; Fracture: Uneven to splintery; Specific Gravity: 2.56-2.58; Fluorescence: Weak olive-green or tan under UV.
Optical Properties
Refractive Index: 1.522–1.530; Birefringence: 0.008; Optically Biaxial negative; exhibits a characteristic schiller or pearly sheen on cleavage faces.
Hardness & Durability
Origin Region
Madagascar, Russia (Ilmen Mountains), Brazil, and the USA (Pikes Peak, Colorado); typically found in granitic pegmatites.
Hardness & Durability
Mohs hardness 6 to 6.5; Brittle toughness; sensitive to pressure and chemicals due to perfect cleavage planes.
Care & Maintenance
Avoid ultrasonic and steam cleaners. Clean with warm soapy water and a soft cloth. Store away from harder stones like quartz to prevent scratching, and avoid prolonged exposure to intense heat.
Rarity & Value
Relatively common; value is determined by the intensity and uniformity of the blue-green color and the absence of brown staining. Rarely treated, though some material may be resin-stabilized.
Special Characteristics
Exhibits perthitic texture (white streaks of albite), occasional weak schiller, and is one of the few green gemstones colored by lead rather than copper or chromium.
Lore & History
Historically known as the 'Stone of Hope.' Used in Ancient Egypt for jewelry and amulets (found in Tutankhamun's treasures). In modern lore, it is believed to soothe the nervous system and align the heart and throat chakras.