Amethyst
Quartz var. Amethyst · Semi-Precious Gemstone
Crystal System
Trigonal, with a typical prismatic habit ending in a pyramid, though this specimen is tumbled.
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2
Formation Process
Hydrothermal and magmatic processes, crystallizing from silica-rich solutions at low to moderate temperatures within cavities in volcanic rocks.
About This Crystal
A small, tumbled, elongated purple and white banded specimen. It is translucent to opaque with a smooth, polished surface and exhibits characteristic chevron or banded color zoning.
Physical Characteristics
Purple and white body color, white streak, no cleavage, conchoidal fracture, specific gravity of approximately 2.65, brittle tenacity, and piezoelectric properties.
Optical Properties
Singly and doubly refractive (uniaxial positive), refractive index of 1.544 to 1.553, weak birefringence, and weak dichroism in shades of purple.
Hardness & Durability
Origin Region
Found globally with notable sources in Brazil, Uruguay, Madagascar, and Zambia. Forms in hydrothermal veins and volcanic gas cavities.
Hardness & Durability
Mohs hardness of 7, making it durable for daily wear in jewelry with good toughness and no distinct cleavage.
Care & Maintenance
Clean with warm soapy water using a soft brush. Avoid harsh chemicals, ultrasonic cleaners, and prolonged direct sunlight to prevent color fading.
Rarity & Value
Common, widely available, and generally affordable, though value increases with deep color saturation and clarity.
Special Characteristics
Displays prominent chevron banding with alternating layers of purple amethyst and white milky quartz.
Lore & History
Historically used by ancient Greeks and Romans as an amulet to prevent intoxication. Associated with the third eye and crown chakras in modern crystal healing, symbolizing peace, clarity, and spiritual growth.