mineral

Massive Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 (Mohs scale), Color: White to transparent/milky, Luster: Vitreous to greasy, Crystal structure: Trigonal (hexagonal system), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified April 7, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: White to transparent/milky, Luster: Vitreous to greasy, Crystal structure: Trigonal (hexagonal system), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and pegmatites. It crystallizes from silica-rich aqueous fluids as they cool in cracks and crevices within host rocks. It is found in all geological ages from Precambrian to recent epochs.

Uses & applications

Used as a gemstone (if clear), source of silicon for electronics, in glass manufacturing, as an abrasive, and widely collected by metaphysical enthusiasts and rockhounds.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. 'Milky' quartz gets its opacity from tiny fluid inclusions (bubbles) of gas or liquid trapped during the crystal's growth.

Field identification & locations

Identify in the field by its ability to scratch glass (hardness 7), lack of cleavage, and characteristic conchoidal (shell-like) fracture. Commonly found in riverbeds, mountains, and near granite outcrops worldwide.