mineral

Tumbled milky quartz (likely chalcedony or quartzite)

Quartz/chalcedony, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness about 7 Mohs; translucent white to pale cream, vitreous-to-waxy luster, cryptocrystalline or microcrystalline structure, and no visible cleavage. The smooth rounded shape is produced by tumbling and polishing.

Identified August 10, 2026More mineral →

Explore Tumbled milky quartz (likely chalcedony or quartzite) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Forms when silica-rich fluids precipitate in cavities, veins, or sediments; quartz deposits range from Precambrian to recent, while chalcedony commonly forms in volcanic cavities. Exact age and locality cannot be determined visually.

Uses & applications

Used as a decorative tumbled stone, lapidary material, carvings, countertops, abrasives, and occasionally jewelry. Common pieces generally have modest collector value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is chemically resistant, though it can develop conchoidal fractures. The specimen may also be pale calcite or another coated stone, which would require testing to confirm.

Field identification & locations

Commonly found worldwide, including Brazil, Madagascar, India, Uruguay, and the United States. Confirm with a glass-scratch test (quartz scratches glass) and, for calcite exclusion, a dilute acid test; avoid damaging valuable specimens.