mineral

Quartz (Milky or Smoky variant)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Translucent white to grayish-tan; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Translucent white to grayish-tan
Luster: Vitreous (glassy)

Identified May 24, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Translucent white to grayish-tan; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins or as a primary constituent of igneous rocks like granite. Its age ranges from Precambrian to recent, depending on the host rock formation. This specimen likely formed from mineral-rich fluids cooling in a cavity.

Uses & applications

Used extensively in glassmaking, electronics (piezoelectric properties), abrasives, and as a semi-precious gemstone in jewelry and decor.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is extremely resistant to weathering, which is why it often remains as pebbles/grains when other rocks erode.

Field identification & locations

Identify by its inability to be scratched by steel, lack of cleavage, and glassy luster. Common in many environments including stream beds, mountains, and beaches. Collectors should look for clean fracture surfaces.

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