Clear Quartz
Quartz var. Rock Crystal · Semi-Precious Gemstone / Decorative Stone
Crystal System
Trigonal; typically occurs as hexagonal prisms with pyramidal terminations; this specimen is carved and polished into a mushroom shape.
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2 (Silicon Dioxide)
Formation Process
Primarily hydrothermal, crystallizing from silica-rich fluids in rock cavities; also forms in igneous pegmatites under varying temperature and pressure.
About This Crystal
A translucent to milky white specimen carved into a mushroom. It exhibits a vitreous luster when polished, with internal clouding, veining, and small fractures typical of natural rock crystal.
Physical Characteristics
Color: Colorless to white; Streak: White; Cleavage: Indistinct; Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Usually inert but can show weak green or yellow under UV if impurities are present.
Optical Properties
Refractive Index: 1.544–1.553; Birefringence: 0.009 (Uniaxial positive); Pleochroism: None; Optical Phenomena: Occasionally shows internal rainbows from fracture interference.
Hardness & Durability
Origin Region
Found globally; major deposits in Brazil, Madagascar, USA (Arkansas), and the Alps within pegmatites and hydrothermal veins.
Hardness & Durability
Mohs Hardness: 7; Toughness: Good (no cleavage); highly durable for jewelry and decorative use; resistant to most household chemicals.
Care & Maintenance
Clean with warm soapy water and a soft brush; safe for ultrasonic and steam cleaning unless heavily fractured; keep away from hydrofluoric acid.
Rarity & Value
Common; value is determined by clarity, size, and the quality of the carving; typically inexpensive as a mass-produced decorative item.
Special Characteristics
Piezoelectric and pyroelectric properties; this specific specimen features internal veining (milky inclusions) that create a 'cloudy' aesthetic.
Lore & History
Historically used for hardstone carving and 'crystal balls'; ancient Greeks believed it was permanently frozen ice (krustallos). In modern lore, it is known as the 'Master Healer' associated with the Crown Chakra.