mineral

Quartz (Milky or Druzy Quartz)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on the Mohs scale. Color: White to translucent with brown/tan iron staining. Luster: Vitreous (glassy) to greasy. Crystal structure: Hexagonal/trigonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: White to translucent with brown/tan iron staining
Luster: Vitreous (glassy) to greasy

Identified March 15, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes where silica-rich hot water cools in veins or cavities within host rocks. It can be found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used in electronics for its piezoelectric properties, as an abrasive in industry, in glassmaking, and frequently as a collector's specimen or lapidary material for jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German 'quarz', which has roots in Slavic words meaning 'hard'. It is resistant to chemical and physical weathering.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife, its lack of cleavage, and the presence of hexagonal crystal points. It is found globally in mountain ranges, riverbeds, and as a primary component of granite.