mineral

Quartz (Common or Milky)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent yellowish; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to translucent yellowish
Luster: Vitreous to greasy

Identified July 8, 2026More mineral →

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Physical properties

Formation & geological history

Formed in various geological environments, commonly through the cooling of silica-rich magma or from hydrothermal veins. It is found in igneous, metamorphic, and sedimentary rocks across all geological ages.

Uses & applications

Widely used in glassmaking, electronics (piezoelectric properties), abrasives, construction sand, and as a common gemstone for jewelry and decorative carvings.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to chemical and physical weathering, which is why it is the primary component of most beach sand.

Field identification & locations

Identify by its hardness (it will scratch glass), its lack of cleavage, and its characteristic waxy or vitreous luster. It is ubiquitous in riverbeds, mountains, and coastal areas worldwide.