mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: white to pale yellowish-tan; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: white to pale yellowish-tan
Luster: Vitreous (glassy) to greasy

Identified July 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: white to pale yellowish-tan; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Quartz forms in a wide variety of environments, commonly crystallizing from cooling magma (igneous) or precipitating from hydrothermal veins. It is found in rocks from almost every geological era due to its extreme chemical and physical stability.

Uses & applications

Used extensively in glassmaking, ceramics, as an abrasive in sandblasting, in electronics (due to piezoelectric properties), and as a gemstone or decorative specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to weathering, which is why it is the primary component of most beach sand.

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), lack of cleavage, and glassy appearance on broken surfaces. It is found globally in mountains, riverbeds, and desert sands.