sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs), Color: Red, brownish-red, Luster: Vitreous to dull, Structure: Trigonal (microcrystalline/cryptocrystalline), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58-2.91

Hardness: 6

Identified June 23, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs), Color: Red, brownish-red, Luster: Vitreous to dull, Structure: Trigonal (microcrystalline/cryptocrystalline), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58-2.91

Formation & geological history

Formed via the deposition of silica from volcanic ash or water in sedimentary environments. Its vibrant red color comes from high concentrations of iron oxide (hematite) inclusions incorporated during the cooling or sedimentation process.

Uses & applications

Widely used for ornamental jewelry, cabochons, decorative carvings, and in alternative healing practices (root chakra). In ancient times, it was used for cylinder seals and amulets.

Geological facts

Red Jasper was known in the ancient world as the 'bringer of courage' and was often used to adorn the breastplates of high priests. It is an opaque variety of chalcedony.

Field identification & locations

Identified by its deep red color, opacity (light does not pass through even thin edges), and its glass-like conchoidal fracture. Common in areas with volcanic activity or ancient seabed deposits like the USA, Brazil, and India.