mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale (scratches glass). Color: Opaque white to cloudy translucent. Luster: Vitreous (glassy) to greasy. Crystal structure: Hexagonal/Trigonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on Mohs scale (scratches glass)
Color: Opaque white to cloudy translucent
Luster: Vitreous (glassy) to greasy

Identified March 16, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions in veins or during the cooling of igneous rock bodies. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in the production of glass, ceramics, and abrasives. High-grade specimens are used in electronics for their piezoelectric properties. Also used in construction aggregate and as a semi-precious stone in jewelry and lapidary work.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. Historically, the cloudy white appearance led ancient observers to believe it was permanent, frozen ice that had become stone.

Field identification & locations

Identify in the field by its white color, ability to scratch glass (hardness), and lack of cleavage (it breaks in irregular, shell-like curves). It is found globally in almost every geological environment, especially in mountain ranges and riverbeds.