mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: white to pale yellow/tan
Luster: Vitreous to greasy

Identified May 17, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. Typically crystallizes from silica-rich magma or precipitates from hydrothermal veins. Often Mesozoic to Cenozoic in age depending on the deposit.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, and as a common landscaping or decorative stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its cloudy appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Found globally in riverbeds, mountains, and mines. Identify by its ability to scratch glass and lack of cleavage planes. Look for a waxy or glassy shine on fresh surfaces.