mineral

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 Mohs; Color: Grayish-white to tan with translucency; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 Mohs
Color: Grayish-white to tan with translucency
Luster: Vitreous (glassy) to greasy

Identified March 21, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Grayish-white to tan with translucency; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It can be found in a wide variety of igneous, metamorphic, and sedimentary environments, ranging from the Precambrian to recent geological ages.

Uses & applications

Used widely in manufacturing glass, ceramics, and electronics (due to piezoelectric properties). Varieties are often used in jewelry, lapidary arts, and as common collector specimens.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is chemically very stable and resistant to weathering, which is why it often remains as the primary component of beach sand.

Field identification & locations

Identify in the field by its hardness (it can scratch glass and steel), lack of cleavage, and characteristic glassy fracture. It is ubiquitous worldwide, especially in granite-rich terrains and riverbeds.