mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white to translucent; 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 from hydrothermal veins. This specimen likely originated from a pegmatite or hydrothermal vein system. Quartz can be found in rocks from virtually any geological age, from Precambrian to recent.

Uses & applications

Used in glassmaking, abrasive blasting, and as a component in electronic quartz oscillators. Low-grade specimens are used in landscaping and construction aggregate; higher quality pieces are used in jewelry (lapidary) or as healing crystals in the metaphysical market.

Geological facts

Milky quartz gets its white, cloudy appearance from tiny fluid inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify in the field by its ability to scratch glass, its milky white color, and the lack of cleavage (it breaks in irregular, shell-like curves). It is found globally in mountainous regions, riverbeds, and as inclusions in granite. For collectors, look for pieces with distinct crystal faces.