mineral

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on the Mohs scale; Color: Colorless to cloudy white; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Colorless to cloudy white
Luster: Vitreous (glassy)

Identified March 5, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Colorless to cloudy white; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. Most commonly crystallizes from cooling magma or precipitates from hydrothermal veins. It is found in geological formations ranging from billions of years old to relatively recent deposits.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction as an abrasive, and widely used in jewelry and gemstone collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks believed clear quartz was fossilized ice that wouldn't melt. It is the defining mineral for '7' on the Mohs scale of mineral hardness.

Field identification & locations

Identify in the field by its hardness (it can scratch glass and steel knives), its lack of cleavage, and its characteristic conchoidal (shell-like) fracture. Commonly found in riverbeds, mountains, and mining sites globally.