mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous to greasy luster, transparent to opaque, conchoidal fracture, no true cleavage, specific gravity of 2.65, trigonal crystal system.

Identified August 4, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to greasy luster, transparent to opaque, conchoidal fracture, no true cleavage, specific gravity of 2.65, trigonal crystal system.

Formation & geological history

Forms in a wide variety of geological environments including igneous, metamorphic, and sedimentary rocks. Often crystallizes from silica-rich hydrothermal solutions or cooling magma.

Uses & applications

Used in electronics, oscillators, glassmaking, abrasive materials, gemstone carving, and mineral specimen collecting.

Geological facts

Quartz is one of the most abundant and widely distributed minerals on Earth's continental crust. It exhibits piezoelectric properties, meaning it can generate an electrical charge when mechanical stress is applied.

Field identification & locations

Can be identified by its characteristic conchoidal fracture, high hardness (scratches glass easily), and hexagonal crystal prism habits when well-formed. Found globally.