mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: Milky white to light beige translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 Mohs
Color: Milky white to light beige translucent
Luster: Vitreous to greasy

Identified July 9, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Milky white to light beige translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Forms through the cooling and crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent of igneous and metamorphic rocks. The milky appearance is caused by tiny fluid inclusions trapped during growth.

Uses & applications

Used in glass making, as an abrasive, in decorative landscaping, and occasionally as a minor gemstone or for metaphysical collecting. Quartz crystals are also vital for their piezoelectric properties in electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. It can sometimes contain trace amounts of gold within its vein structures.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), its lack of cleavage, and its waxy/greasy luster when fractured. Frequently found in riverbeds and mountainous terrain.