Milky Quartz
Quartz (Variety: Milky Quartz) · Mineral Specimen / Semi-Precious Gemstone
Crystal System
Trigonal; typically hexaganol-prism habit, though the specimen shown is massive and irregular
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2
Formation Process
Primarily Hydrothermal; forms from silica-rich fluids in veins or as a primary mineral in igneous pegmatites
About This Crystal
An opaque to translucent white variety of quartz. It has a vitreous to greasy luster and appears cloudy due to millions of microscopic fluid inclusions of gas or liquid trapped during crystal growth.
Physical Characteristics
Color: White/Cloudy; Streak: White; Cleavage: None (Indistinct); Fracture: Conchoidal to uneven; Specific Gravity: 2.65; Fluorescence: Usually none, occasionally weak yellow or green
Optical Properties
Refractive Index: 1.544-1.553; Birefringence: +0.009; No pleochroism; Doubly refractive; generally lacks fire or dispersion
Hardness & Durability
Origin Region
Globally abundant; notable sources include Brazil, USA (Arkansas/New York), Madagascar, and the Alps in Europe
Hardness & Durability
Mohs Hardness: 7; Toughness: Good (very durable for jewelry); Stability: High, resistant to most household chemicals and light
Care & Maintenance
Safe with warm soapy water; resistant to ultrasonic cleaners; avoid hydrofluoric acid; store separately only to prevent scratching softer stones
Rarity & Value
Common; very affordable. Value is generally low unless it contains gold inclusions or forms aesthetically pleasing crystals
Special Characteristics
Cloudy appearance caused by fluid inclusions (Tyndall scattering); may contain phantom growth layers or rutilated needles in rare cases
Lore & History
Historically used as a 'placeholder' stone in ancient carvings; traditionally associated with the Crown Chakra and believed to represent purity and clarity of mind in folklore