mineral

Quartz (Milky/Crystalline)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to semi-opaque clear; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to semi-opaque clear
Luster: Vitreous/Glassy

Identified April 2, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to semi-opaque clear; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed from hydrothermal veins, cooling of silica-rich magma, or as a secondary mineral in various rock types. It is one of the most abundant minerals and can vary in age from millions to billions of years depending on the host rock.

Uses & applications

Used in electronics (as a piezoelectric material), glass manufacturing, abrasives, jewelry (as semi-precious stones), and widely collected by enthusiasts.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is perfectly clear, but impurities or inclusions of gas/liquid create the 'milky' appearance seen in this specimen.

Field identification & locations

Identify by its hardness (it will scratch glass and steel), lack of cleavage, and its typical hexagonal crystal habits. Found commonly in mountainous regions, riverbeds, and as veins in metamorphic rocks.