Amethyst
Quartz var. Amethyst · Semi-Precious Gemstone
Crystal System
Trigonal, with a macrocrystalline habit forming prismatic crystals, commonly appearing here as a tumbled and polished pebble with visible fractures.
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2
Formation Process
Hydrothermal and magmatic processes, precipitating from silica-rich aqueous solutions within cavities in volcanic rocks at low to moderate temperatures.
About This Crystal
This is a tumbled, polished specimen of purple quartz showing translucent to transparent areas, a distinct internal fracture running through the middle, and characteristic color zoning ranging from pale lavender to deeper violet.
Physical Characteristics
Light purple to violet body color, white streak, no true cleavage, conchoidal fracture, specific gravity around 2.65, brittle tenacity, and typically inert under UV light though may show faint green or yellow fluorescence in rare cases.
Optical Properties
Singly or doubly refractive with a low birefringence of 0.009, uniaxial positive optical character, and weak dichroism displaying reddish-purple and bluish-purple hues from different angles.
Hardness & Durability
Origin Region
Brazil, Uruguay, Madagascar, and Zambia, typically forming within hollow volcanic geodes and hydrothermal veins.
Hardness & Durability
Mohs hardness of 7, making it durable enough for general jewelry wear, though it lacks cleavage, it can be sensitive to sharp impacts along internal fracture planes.
Care & Maintenance
Clean with warm soapy water using a soft brush, avoid harsh chemicals and ultrasonic cleaners due to fractures, and store away from prolonged direct sunlight to prevent color fading.
Rarity & Value
Common to moderately rare depending on saturation and clarity; valued primarily on deep purple color saturation, transparency, and lack of inclusions, with treatments like heat-treatment to yellow citrine being common.
Special Characteristics
Exhibits distinct color banding and natural internal fracturing with piezoelectric and pyroelectric properties.
Lore & History
Historically worn by ancient Greeks and Romans to prevent intoxication, associated with royalty, peace, and spiritual growth, commonly linked to the Third Eye and Crown chakras in modern crystal healing lore.