mineral

Tumbled white chalcedony (likely milky quartz)

Chalcedony, microcrystalline SiO₂; possibly milky quartz

AI-generated identification · may be incorrect

Hardness 6.5–7 Mohs; translucent white to pale gray, waxy-to-vitreous luster, no visible cleavage, cryptocrystalline quartz structure, specific gravity about 2.6. The smooth oval shape indicates machine tumbling and polishing.

Identified August 13, 2026More mineral →

Explore Tumbled white chalcedony (likely milky quartz) 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 fill cavities and fractures, depositing microscopic quartz fibers; specimens may range from ancient volcanic-hosted deposits to younger sedimentary veins. Exact age and locality cannot be determined from the photograph.

Uses & applications

Used as an inexpensive ornamental stone, cabochon, lapidary material, and metaphysical collectible; chalcedony varieties are also used in jewelry and decorative objects.

Geological facts

Milky appearance results from microscopic inclusions, fluid, or light scattering. It may be confused with white jade, opalite glass, or calcite.

Field identification & locations

Identify with hardness: it should scratch ordinary glass, while calcite will not; quartz has no reaction to dilute acid. Common sources include Brazil, India, Madagascar, Uruguay, and the United States.