mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Translucent white to milky white; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Translucent white to milky white
Luster: Vitreous to greasy

Identified March 20, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Translucent white to milky white; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments, most commonly from the crystallization of molten magma or through hydrothermal activity in veins. It can be found in rocks from all geological eras.

Uses & applications

Commonly used in glassmaking, abrasives, and as a concrete additive in construction. In its pure or polished form, it is used for jewelry, lapidary work, and electronics (due to piezoelectric properties).

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, it was used by many cultures to create tools such as arrowheads and scrapers due to its hardness and sharp edges when broken.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and lack of cleavage (it breaks into irregular, curved flakes). It is found globally in riverbeds, mountains, and as a major component of granite.