mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

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

Identified April 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions or magma. Milky quartz gets its characteristic white color from microscopic inclusions of fluids or gas trapped during crystal growth. It can be found in veins or as a component of igneous, metamorphic, and sedimentary rocks across all geological ages.

Uses & applications

Used widely in glass making, ceramics, and abrasives. High-purity quartz is essential in electronics for its piezoelectric properties. In lapidary, it is used for carvings, beads, and as a collector's specimen.

Geological facts

Quartz is the most abundant mineral on the Earth's continental crust. Pure quartz is clear, but milky quartz is the most common variety found in nature due to internal imperfections.

Field identification & locations

Identify in the field by its ability to scratch glass (Hardness 7), its lack of cleavage, and its waxy or vitreous luster. It is commonly found in gravel pits, mountain streams, and within granite outcrops. Collectors should look for distinct crystal faces versus smooth river-worn 'pebbles'.