mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to cream
Luster: Vitreous to greasy

Identified May 29, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms through crystallization from molten magma or precipitation from hot hydrothermal veins. This specimen likely originated from a quartz vein in igneous or metamorphic rock. Found throughout Earth's history across all geological ages.

Uses & applications

Used extensively in glassmaking, abrasives, electronic oscillators (piezoelectric properties), and as architectural aggregate or ornamental stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz gets its opaque white color from tiny bubbles of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and common occurrence in veins. Often found in riverbeds or eroded from rocky outcrops.