mineral

Milky quartz

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Typically white to translucent with a vitreous-to-greasy luster and irregular fracture; Mohs hardness 7, no cleavage, and specific gravity about 2.65. The specimen appears massive and quartz-rich, with some tan iron-oxide staining or attached matrix.

Identified September 2, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids or late-stage igneous fluids fill fractures and cavities, and also occurs in veins within older igneous and metamorphic rocks. Quartz is geologically widespread and may form from Precambrian through recent processes.

Uses & applications

Used for glass, ceramics, engineered stone, abrasives, and electronics; attractive translucent pieces are collected or used decoratively, though this rough specimen is not usually gem grade.

Geological facts

Quartz is one of Earth’s most abundant minerals and has a hexagonal crystal structure, even when crystals are not visible. Milky appearance results mainly from microscopic fluid inclusions and structural defects.

Field identification & locations

Identify it by its hardness— it should scratch ordinary glass—lack of cleavage, pale translucent body, and conchoidal or irregular fracture; a steel nail should not scratch it. Common in quartz veins worldwide, including Brazil, the United States, India, Madagascar, and Australia.