Amethyst
Quartz var. Amethyst · Semi-Precious Gemstone
Crystal System
Trigonal, with a hexagonal crystal system framework; typically forms prismatic crystals terminating in six-sided pyramids or as massive geodes and druzy crusts.
Mineral Group
Silicates (Subgroup: Tectosilicates)
Chemical Formula
SiO2
Formation Process
Hydrothermal and igneous processes where silica-rich solutions fill cavities in volcanic rocks (gas cavities/vesicles in basalt) at low to moderate temperatures, incorporating trace amounts of iron subjected to natural irradiation.
About This Crystal
The specimen is set as a polished cabochon or flat stone within a silver-colored 'Tree of Life' pendant mounting. It exhibits a deep purple color, characteristic of amethyst, with areas of translucent to opaque translucency and a vitreous to waxy luster on polished surfaces. Natural color zoning and internal cloudiness or minor inclusions may be present beneath the metal wirework.
Physical Characteristics
Color ranges from pale lilac to deep purple; streak is white; crystal habit is typically microcrystalline or macrocrystalline quartz masses; cleavage is absent; fracture is conchoidal; specific gravity is approximately 2.65; tenacity is brittle; exhibits piezoelectric properties.
Optical Properties
Refractive index ranges from 1.544 to 1.553; uniaxial positive optical character; birefringence is 0.009; typically weak to moderate pleochroism showing reddish-purple and bluish-purple hues from different angles.
Hardness & Durability
Origin Region
Notable sources include Brazil, Uruguay, Madagascar, Zambia, and the United States (such as Arizona and Colorado). Forms primarily in volcanic rock cavities or hydrothermal veins.
Hardness & Durability
Mohs hardness rating of 7; fair to good durability for jewelry use, though susceptible to scratching by harder minerals like topaz or corundum; lacks cleavage, reducing risk of splitting along planes.
Care & Maintenance
Can be cleaned safely with warm soapy water and a soft brush; avoid harsh chemicals and prolonged exposure to direct sunlight, which can cause the purple color to fade over time; store separately to prevent scratching softer stones.
Rarity & Value
Common to moderately rare depending on saturation, clarity, and size; deep purple Siberian-grade or top Uruguayan material commands higher prices, while commercial grades used in standard jewelry settings are affordable and widely available.
Special Characteristics
Natural color zoning (chevron patterns), potential for faint yellowish heat-treated transition to citrine, and piezoelectric properties under mechanical stress.
Lore & History
Historically worn in ancient times to prevent drunkenness and ensure a clear head; associated with royalty and spiritual protection. In modern metaphysical practices, it is commonly linked to the third eye and crown chakras, believed to promote calm, clarity, and spiritual growth.