mineral

Milky quartz (iron-stained quartz)

Quartz, SiO₂ (trigonal crystalline silica)

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent white to honey-brown with a vitreous-to-dull luster. The massive specimen has no obvious cleavage and typically breaks with irregular or conchoidal fracture; brown color likely comes from iron-oxide staining.

Identified October 15, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystallizes from silica-rich fluids in veins and cavities, or forms as a constituent of many igneous and metamorphic rocks. Quartz deposits occur across geologic time, so the specimen’s age cannot be determined from the image.

Uses & applications

Quartz is used in glassmaking, electronics, abrasives, and construction materials; attractive pieces are collected or used decoratively.

Geological facts

Quartz is one of Earth’s most abundant minerals and has a Mohs hardness of 7, so it can scratch ordinary glass.

Field identification & locations

Look for glassy areas, lack of cleavage, and hardness sufficient to scratch glass; common sources include hydrothermal veins and granites worldwide. The image shows a rough, massive quartz-like specimen, but identification is visual only.