mineral

Quartz / Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous (glassy)

Identified April 16, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the crystallization of silica-rich molten rock (magma) or from hydrothermal veins. It can be found in almost all geological environments and across all geological ages, often as a primary mineral in igneous rocks like granite.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), construction as an aggregate, and widely as a semi-precious gemstone in jewelry and for specimen collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), lack of cleavage, and glassy appearance on fresh surfaces. It is found globally in mountains, riverbeds, and beach sand.