mineral

Quartz (Milky or Smoky Quartz)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Translucent white to grey/yellowish; Luster: Vitreous (glassy) to greasy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent white to grey/yellowish
Luster: Vitreous (glassy) to greasy

Identified April 7, 2026More mineral →

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Physical properties

Formation & geological history

Formed in a wide variety of environments, most commonly from the cooling of silica-rich magma or from hydrothermal veins. It can be found in igneous, metamorphic, and sedimentary rocks across all geological ages.

Uses & applications

Used in electronics (as a piezoelectric material), glass making, abrasives, construction sand, and as a gemstone in jewelry or for decorative carvings.

Geological facts

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

Field identification & locations

Identify by its ability to scratch glass (hardness 7), its lack of cleavage (it breaks into irregular, curved shards), and its glassy luster. It can be found nearly everywhere, particularly in mountainous regions or creek beds.