mineral

Tumbled yellow-brown quartz-rich stone, possibly jasper

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide impurities

AI-generated identification · may be incorrect

Opaque mustard-yellow to tan, smoothly rounded and matte-to-waxy; quartz hardness is about 7 Mohs, with no visible cleavage and conchoidal fracture. The granular appearance and iron staining are consistent with jasper, though the photo cannot confirm composition.

Identified August 26, 2026More mineral →

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Physical properties

Formation & geological history

Likely formed when silica-rich fluids filled fractures or replaced sediment, with iron oxides producing the yellow-brown color; commonly Precambrian to younger. Its rounded shape indicates human tumbling or natural abrasion.

Uses & applications

Used for inexpensive cabochons, beads, carvings, lapidary pieces, and decorative stone; not typically used as a major construction aggregate.

Geological facts

Jasper is an opaque variety of chalcedony and may contain hematite, goethite, clay, or other inclusions. A glass-scratching test can support quartz identification, but it may damage the specimen.

Field identification & locations

Commonly found in silica-rich volcanic and sedimentary terrains, including the western United States, Australia, Brazil, India, and Madagascar. Confirm with hardness, a waxy fracture, and absence of acid reaction; yellow jasper can resemble petrified wood or iron-stained chert.