mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Identified April 9, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and pegmatites when silica-rich fluids cool and crystallize. It is one of the most common minerals in the Earth's crust, found in geological environments ranging from Precambrian to recent ages.

Uses & applications

Used in construction as aggregate, in glass manufacturing, and as a source of silicon for electronics. Lower quality specimens are used for landscaping or as decorative stones.

Geological facts

The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It is a major component of granite and many other igneous and metamorphic rocks.

Field identification & locations

Identify by its white color, inability to be scratched by a steel knife, and lack of cleavage (breaks like glass). It is found globally in mountains, riverbeds, and beaches.