Mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to opaque/cloudy; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White to opaque/cloudy
Luster: Vitreous to greasy

Identified April 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to opaque/cloudy; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust and can be found in rocks of all geological ages.

Uses & applications

Used in glassmaking, abrasives, electronics (due to piezoelectric properties), construction as aggregate, and in landscaping or jewelry as decorative stones.

Geological facts

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

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), lack of cleavage, and characteristic waxy or glassy appearance. It is found globally in many environments, particularly in mountainous regions and riverbeds.