mineral

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: Colorless to white/translucent
Luster: Vitreous (glassy) to greasy

Identified April 2, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of magma or from hydrothermal veins. It is found in almost all geological environments and across all geological ages, often as the last mineral to crystallize in igneous rocks.

Uses & applications

Used in glass manufacturing, electronics (piezoelectric properties), abrasives, construction as an aggregate, and widely used in jewelry and gemstone collections.

Geological facts

Quartz is the second most abundant mineral in the Earth's continental crust. It exists in many varieties including amethyst, citrine, and rose quartz. Ancient Greeks believed quartz was ice that had frozen so hard it would never melt.

Field identification & locations

Identify by its ability to scratch glass, lack of cleavage, and conchoidal (shell-like) fracture. Look for it in granite outcrops, riverbeds, or as veins in metamorphic rocks. Use a hardness test to distinguish from calcite (which is softer).