sedimentary

Red Jasper

Silicon Dioxide with Hematite (SiO2 + Fe2O3)

Hardness: 6.5-7 (Mohs scale); Color: Bricky red to deep brownish-red; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline/cryptocrystalline); Cleavage: None; Conchoidal fracture; Specific gravity: 2.58-2.91.

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

Identified June 21, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of fine silica-rich materials and iron oxides. Usually occurs in hydrothermal veins or as a secondary mineral in volcanic rocks and sedimentary deposits via silica-rich groundwater precipitation.

Uses & applications

Primarily used as a gemstone for jewelry, cabochons, beads, and decorative ornaments. Historically used for seals, talismans, and as a material for knapping tools.

Geological facts

The red color is caused by impurities of iron (hematite). In ancient civilizations, it was known as the 'rain bringer' and was frequently mentioned in various religious texts and mythologies as a stone of protection and strength.

Field identification & locations

Identify by its opaque nature (unlike carnelian which is translucent) and dull waxy to vitreous luster. Commonly found in riverbeds or beaches where silica-rich rocks weather out. Major deposits are in India, Brazil, Madagascar, and the southwestern USA.

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