Milky Quartz
Quartz (Variety: Milky Quartz) · Mineral Specimen / Decorative Stone
Crystal System
Trigonal; typically found in massive habit when water-worn, as seen in this river-tumbled specimen
Mineral Group
Silicates (Subgroup: Tectosilicates)
Chemical Formula
SiO2 (Silicon Dioxide) with fluid inclusions
Formation Process
Primarily Hydrothermal; forms in veins as silica-rich fluids cool. Can also be Igneous (magma) or Metamorphic.
About This Crystal
An opaque to translucent white or tan specimen with a waxy to vitreous luster. The surface is smooth and rounded from water erosion, showing fine internal fractures and brownish iron-oxide staining.
Physical Characteristics
Color: White to off-white; Streak: White; Cleavage: None (poor); Fracture: Conchoidal; Specific Gravity: 2.65; Fluorescence: Usually none; Luster: Waxy to Greasy when wet.
Optical Properties
Uniaxial positive; Refractive Index: 1.544-1.553; Birefringence: 0.009; No significant pleochroism or dispersion in this opaque variety.
Hardness & Durability
Origin Region
Found globally; major deposits in Brazil, USA (Arkansas), and Alpine regions. This specimen appears to be a river-tumbled cobble.
Hardness & Durability
Mohs Hardness: 7; Very durable; Toughness is high due to the lack of cleavage, though thermal shock can cause fracturing.
Care & Maintenance
Extremely stable; can be cleaned with warm soapy water and soft brushes. Safe for ultrasonic cleaners unless heavily fractured.
Rarity & Value
Very Common; low monetary value as a bulk mineral specimen, though aesthetically pleasing river stones are used in landscaping or craft jewelry.
Special Characteristics
Microscopic fluid inclusions (gas/liquid) are responsible for the 'milky' turbidity; lacks the transparency of rock crystal.
Lore & History
Historically used for tools and ornaments since the Stone Age. In modern lore, it is associated with clarity and gentle energy, often linked to the Crown Chakra.