mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear to greenish-gray in this specimen; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to greenish-gray in this specimen
Luster: Vitreous (glassy)

Identified June 9, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to greenish-gray in this specimen; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Quartz forms in a wide variety of environments, including igneous crystallization in pegmatites, metamorphic recrystallization, and sedimentary precipitation from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust.

Uses & applications

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

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Greenish varieties are often called Prasiolite, though natural green quartz is rare compared to heat-treated varieties.

Field identification & locations

Identify in the field by its hardness (will scratch glass), lack of cleavage, and glassy appearance. It is found globally in almost all rock types and geographic regions.