mineral

Milky quartz with iron-oxide staining and matrix

Quartz, silicon dioxide (SiO₂), likely massive quartz

AI-generated identification · may be incorrect

Typically hardness 7, vitreous to waxy luster, white to translucent color, conchoidal fracture, and no cleavage; the brown patches are likely iron oxides or host-rock inclusions. Crystal form is difficult to see because the quartz is massive rather than well crystallized.

Identified August 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed when silica-rich hydrothermal fluids filled fractures or cavities and crystallized, commonly in veins within igneous or metamorphic rocks. Quartz veins range from ancient Precambrian rocks to geologically recent formations.

Uses & applications

Used as a silica source for glass, ceramics, and engineered stone; attractive pieces may be collected or polished, though this specimen appears mainly ornamental rather than gem quality.

Geological facts

Milky quartz gets its cloudy appearance from microscopic fluid inclusions, fractures, or mineral impurities. Iron oxidation commonly produces the orange-brown staining visible here.

Field identification & locations

Common worldwide, including Brazil, the United States, Madagascar, and the Alps. Identify it by its glassy appearance, hardness greater than a steel knife, lack of cleavage, and inability to scratch it with a steel nail; exact identification would benefit from a close-up or hardness test.