sedimentary

Red Jasper

Argillaceous microcrystalline quartz (SiO2 with Fe2O3 inclusions)

Hardness: 6.5-7 (Mohs scale); Color: Brick red to brownish-red; Luster: Vitreous to dull; Crystal structure: Hexagonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Brick red to brownish-red
Luster: Vitreous to dull

Identified February 19, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed via the deposition of silica-rich fluids in volcanic or sedimentary environments. Its red color comes from high concentrations of iron oxide (hematite) during its formation process, which can date back to several million years depending on the deposit site.

Uses & applications

Commonly used in lapidary work for making cabochons, beads, and decorative ornaments. Historically used for seals, jewelry, and ritual objects. It is also a popular stone for tumbling and collectors.

Geological facts

Red Jasper was known as a 'warrior's stone' in ancient times, believed to provide physical strength and protection. It is a dense, opaque variety of chalcedony.

Field identification & locations

Identify in the field by its opaque reddish appearance and smooth, rounded surface when found as river cobbles. It will scratch glass but cannot be scratched by a steel pocket knife. Commonly found in riverbeds, desert washes, and volcanic regions globally, including the USA, India, and Brazil.

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