mineral

Quartz (Milky or Druzy Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to translucent tan; Luster: Vitreous to greasy; Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to translucent tan
Luster: Vitreous to greasy

Identified May 7, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to translucent tan; Luster: Vitreous to greasy; Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed via hydrothermal activity where silica-rich fluids cool and crystallize in rock cavities and veins; common in many geological ages and environments like igneous intrusions and sedimentary deposits.

Uses & applications

Used in electronics as a piezoelectric material, glassmaking, construction as an abrasive, and extensively in jewelry or as decorative rough specimens for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to both chemical and physical weathering.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and typical crystal habits. Found worldwide, particularly in riverbeds and mountainous terrain.