mineral

Quartz (Smoky/Milky variant)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Grayish-white to smoky; Luster: Vitreous to greasy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Grayish-white to smoky
Luster: Vitreous to greasy

Identified June 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Grayish-white to smoky; Luster: Vitreous to greasy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed from the cooling of silica-rich magma or through hydrothermal veins. This specimen shows signs of mechanical weathering and may have been part of a larger vein or granite outcrop.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, and as a semi-precious gemstone in jewelry.

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 is so common in riverbeds and on beaches.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), its lack of cleavage, and its characteristic waxy or glassy luster. Found globally in almost all geological environments.