mineral

Quartz (Milky or Cloudy variety)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Translucent white to gray with iron staining (brownish-orange), Luster: Vitreous (glassy) to greasy, Crystal structure: Trigonal/Hexagonal prism, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified April 6, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. This specimen appears to be a 'vein quartz' fragment, often found in igneous or metamorphic host rocks and released through erosion.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as decorative gravel. Lower quality pieces are used in construction as aggregate.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Iron oxide inclusions (seen as the brown streaks here) are very common and can lead to the formation of 'Golden Healer' quartz or Citrine under different conditions.

Field identification & locations

Identify in the field by its inability to be scratched by steel, lack of cleavage, and common occurrence in pebbles or veins. Found globally in almost all geological environments.

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