mineral

Quartz (Milk or Ice Quartz)

Silicon Dioxide (SiO2)

Hardness: 7.0 on Mohs scale. Color: Transparent to translucent white. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7
Color: Transparent to translucent white
Luster: Vitreous (glassy)

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7.0 on Mohs scale. Color: Transparent to translucent white. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Formed from silica-rich hydrothermal solutions or cooling magma in veins and pegmatites. It is the most abundant mineral in the Earth's continental crust and occurs throughout all geological eras.

Uses & applications

Used in the production of glass, ceramics, abrasives, and as a component in concrete. High-purity quartz is essential for making silicon wafers in electronics and watches. It is popular in jewelry and for decorative lapidary work.

Geological facts

Quartz is piezoelectric, meaning it generates an electric charge when mechanical stress is applied. This property makes it vital for keep time in quartz clocks and watches.

Field identification & locations

Identify by its hardness (it can scratch glass and steel) and its conchoidal (shell-like) fracture patterns. It is found globally, common in riverbeds and mountainous terrain. Collectors look for clarity and internal fractures that create 'rainbows'.