Amethyst
Quartz var. Amethyst · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal; typically prismatic but shown here in a crystalline drusy/mass aggregate habit.
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2 (Silicon Dioxide with traces of Iron Fe3+)
Formation Process
Magmatic/Hydrothermal; forms from silica-rich fluids in volcanic cavities (vugs) or hydrothermal veins at low to moderate temperatures.
About This Crystal
This specimen shows a cluster of translucent to transparent light violet crystals. It displays a vitreous (glassy) luster with visible crystal facets. The color is distributed unevenly, which is typical for small quartz points.
Physical Characteristics
Color: Pale violet to lavender; Streak: White; Cleavage: None (indistinct); Fracture: Conchoidal; Density: 2.65 g/cm3; Some specimens may show weak fluorescence under UV.
Optical Properties
Refractive Index: 1.544–1.553; Birefringence: 0.009 (uniaxial positive); Pleochroism: Weak (purple/reddish-purple); No significant dispersion.
Hardness & Durability
Origin Region
Notable sources include Brazil (Rio Grande do Sul), Uruguay (Artigas), Madagascar, and Zambia. Often found in basaltic geodes.
Hardness & Durability
Mohs Hardness: 7; Toughness: Fair to Good; Highly durable for most jewelry, though heat-sensitive.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid ultrasonic cleaners and steam. Should be kept out of direct sunlight to prevent color fading.
Rarity & Value
Common; value is determined by color intensity (deep 'Siberian' purple being most valuable), clarity, and size. Generally affordable.
Special Characteristics
Color zoning is common. This specimen appears to have a drusy or crystalline mass texture with light-reflecting internal fractures and facets.
Lore & History
Historically used by the Ancient Greeks to prevent intoxication ('amethystos' means 'not drunk'). In metaphysical lore, it is associated with the Third Eye and Crown chakras, believed to promote calm, clarity, and spiritual protection.