mineral

Tumbled quartz (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; white to translucent with a vitreous-to-waxy luster, conchoidal fracture, and no cleavage. The rounded shape is mechanically polished; surface inclusions or iron staining are visible.

Identified August 30, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystallizes from silica-rich igneous and hydrothermal fluids, and also occurs in metamorphic veins and sedimentary rocks. Most quartz formed over broad geologic timescales, commonly millions to billions of years old.

Uses & applications

Used for ornamental tumbled stones, carvings, countertops, glass, electronics, abrasives, and ceramics; this specimen has modest lapidary or metaphysical-collecting value.

Geological facts

Milky appearance results from microscopic fluid or gas inclusions and structural defects scattering light. Quartz is one of Earth’s most abundant and chemically durable minerals.

Field identification & locations

Common worldwide, including Brazil, Madagascar, the United States, and China. Identify it by its glassy translucence, hardness, lack of cleavage, and inability to be scratched by a steel knife; a streak test is white.