mineral

Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, clear to milky white color, vitreous to greasy luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 3, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, clear to milky white color, vitreous to greasy luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

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

Uses & applications

Widely used in electronics, oscillators, glassmaking, abrasives, and as a semi-precious gemstone or decorative specimen.

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 in response to applied mechanical stress.

Field identification & locations

Easily identified by its hardness (scratches glass), conchoidal fracture, and lack of cleavage. It is extremely common worldwide and very abundant in the Mid-Atlantic region of the US (near 40.0°N, 75.1°W), making this a highly plausible local find.