mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Transparent to white, milky, gray, or various other colors depending on impurities. Luster: Vitreous (glassy). Crystal Structure: Trigonal. Cleavage: None (exhibits conchoidal fracture). Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Luster: Vitreous (glassy)

Identified August 5, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. It is a primary component of pegmatites, hydrothermal veins, and sandstones, crystallizing from silica-rich melts or solutions over geological timescales.

Uses & applications

Widely used in electronics (oscillator crystals), glassmaking, abrasives, gemstones, and construction materials.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. Due to its piezoelectric properties, quartz crystals are used in watches and various electronic devices to generate precise frequency signals.

Field identification & locations

Easily identified by its hardness of 7 (it easily scratches glass and cannot be scratched by a steel knife) and its characteristic conchoidal fracture. Found globally in almost all types of geological formations.