mineral

Tumbled yellow chalcedony or quartz

Chalcedony (microcrystalline SiO₂), possibly iron-stained quartz

AI-generated identification · may be incorrect

Hardness 6.5–7 Mohs; translucent honey-yellow to brown, with a waxy to subtly vitreous luster and no obvious cleavage. The rounded, water-worn shape and cloudy internal texture suggest microcrystalline quartz rather than glass.

Identified August 16, 2026More mineral →

Explore Tumbled yellow chalcedony or 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

Silica-rich groundwater deposited quartz in volcanic cavities or sedimentary fractures; yellow coloration commonly comes from iron oxides. Formation may range from millions to hundreds of millions of years old, depending on host rock.

Uses & applications

Used as a lapidary stone, cabochon, bead, or collectible; attractive material may be sold as yellow chalcedony or citrine-like quartz.

Geological facts

The image cannot reliably distinguish chalcedony from citrine, yellow jasper, or resin-coated material without testing. Chalcedony commonly has a waxier appearance and tougher fracture than crystalline quartz.

Field identification & locations

Common sources include Brazil, Uruguay, Madagascar, India, and the western United States. Check for glass-like conchoidal fracture, hardness against steel, and lack of bubbles; a gemological refractive-index test is more definitive.