mineral

Milky quartz (tumbled quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Mohs hardness 7; white to translucent with a vitreous-to-waxy luster, irregular conchoidal fracture, and no cleavage. The rounded shape indicates tumbling or water-worn abrasion; internal haziness comes from microscopic inclusions or fractures.

Identified August 18, 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 rocks and veins. Its exact age cannot be determined from the photograph; quartz specimens range from recent deposits to Precambrian formations.

Uses & applications

Commonly used for ornaments, carvings, countertops, abrasives, glass, and electronics; attractive translucent pieces are sold as inexpensive lapidary material.

Geological facts

Milky quartz is one of the most abundant quartz varieties and commonly forms massive, nontransparent masses rather than well-developed crystals.

Field identification & locations

Identify it by its glassy appearance, hardness sufficient to scratch ordinary glass, lack of cleavage, and conchoidal fracture; common sources include Brazil, Madagascar, the United States, and worldwide quartz veins.