mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to colorless/transparent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to colorless/transparent
Luster: Vitreous to greasy

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White to colorless/transparent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Quartz forms in a wide variety of environments, most commonly from the cooling of magma (igneous) or precipitation from hydrothermal veins. It is a major component of granite and many metamorphic rocks. This specimen is likely a piece of milky quartz vein material.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), abrasives, construction as aggregate, and widespread use as gemstones 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 greasy luster on fractured surfaces. It is found globally in almost every geological setting.