sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Hardness: 6.5-7 (Mohs scale); Color: Bricky-red to brownish-red; Luster: Vitreous to dull; Crystal Structure: Microcrystalline (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91

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

Identified January 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica from hydrothermal solutions or volcanic ash into sedimentary environments. Its red color is derived from iron (hematite) inclusions that occur during the silicification process.

Uses & applications

Predominantly used as a gemstone for jewelry (cabochons, beads), decorative carvings, and in the practice of lapidary arts. Historically used for making tools due to its hardness and fracture pattern.

Geological facts

Jasper was a favorite gem in antiquity and is mentioned in many ancient scriptures and myths. It is known as the 'Supreme Nurturer' in metaphysical circles. In geological terms, it is an opaque variety of chalcedony.

Field identification & locations

Identify in the field by its deep red color, total opacity (it does not transmit light even at the edges), and smooth, waxy feel when water-worn. Common locations include India, Brazil, Egypt, and the Southwestern United States.

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