mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous (glassy) to greasy

Identified March 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments, most commonly from the cooling of silica-rich magma or hydrothermal veins. It is found in igneous, metamorphic, and sedimentary rocks across all geological ages, often concentrated in quartz veins.

Uses & applications

Used extensively in the glassmaking and abrasive industries. High-purity quartz is used in electronics for its piezoelectric properties. Common specimens are used for landscaping, construction aggregate, and as 'pocket stones' for collectors.

Geological facts

The milky white color is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz found on the Earth's surface.

Field identification & locations

Identify in the field by its white color, ability to scratch glass (hardness 7), and lack of cleavage (it breaks in irregular, shell-like curves). It is found globally, often in mountain ranges or riverbeds.