Amethyst
Quartz var. Amethyst · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal system; typically occurs as hexagonal prisms terminated by rhombohedra. This specimen shows a druzy habit within a geode structure carved into a heart shape.
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2 (Silicon Dioxide) with trace amounts of Iron (Fe3+) and irradiation centers
Formation Process
Hydrothermal/Magmatic: Forms from silica-rich fluids cooling in volcanic gas bubbles (vesicles) at relatively low temperatures (50-250°C).
About This Crystal
A heart-shaped carving of a natural amethyst druse. Features numerous small, interlocking prismatic crystals with a vitreous (glassy) luster. Color ranges from pale lavender to medium purple with some white/clear quartz at the base. Clusters are translucent to transparent.
Physical Characteristics
Color: Purple/Violet; Streak: White; Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Generally inert or weak greenish-blue under UV.
Optical Properties
Refractive Index: 1.544-1.553; Birefringence: 0.009; Optical Character: Uniaxial positive; Pleochroism: Weak to moderate purple and reddish-purple.
Hardness & Durability
Origin Region
Brazil (Rio Grande do Sul) or Uruguay are common for this type of druzy geode material; forms in volcanic basalt cavities.
Hardness & Durability
Mohs Hardness: 7.0; Toughness: Good (though druzy clusters can be brittle and prone to chipping); Stability: Sensitive to high heat and prolonged direct sunlight.
Care & Maintenance
Clean with warm soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaning as they can loosen crystals in a druse. Store away from direct sunlight to prevent color fading.
Rarity & Value
Common; Value depends on color depth (deeper purple is higher value), crystal size, and clarity. Carved shapes like this are mass-produced but popular for gifts.
Special Characteristics
Color zoning is often visible in individual crystals. It exhibits piezoelectricity. This specific specimen is an 'enhydre' candidate if water was trapped in the cavity, though unlikely in a small carving.
Lore & History
Historically worn by Ancient Greeks to prevent intoxication (from 'amethystos', meaning 'not intoxicated'). Spiritually associated with the Crown Chakra, peace, and protection in modern alternative healing traditions.