sedimentary

Red Jasper

Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)

Hardness: 6.5-7 (Mohs scale); Color: Brick red to brownish red due to hematite; Luster: Vitreous to waxy; Crystal structure: Microcrystalline/Cryptocrystalline (Trigonal); Cleavage: None; Specific gravity: 2.58-2.91

Hardness: 6
Color: Brick red to brownish red due to hematite
Luster: Vitreous to waxy

Identified April 22, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the deposition of silica from mineral-rich waters into cavities or through the chemical replacement of volcanic ash or sediments. It typically occurs in hydrothermal environments or sedimentary layers often associated with iron-rich deposits.

Uses & applications

Commonly used as a gemstone in jewelry (cabochons, beads), for carvings, as an ornamental stone in interior decoration, and highly valued by collectors of lapidary rough or tumbled stones.

Geological facts

Red Jasper has been used since antiquity; it was known as the 'rain bringer' in some Native American traditions and was highly prized in ancient Egypt for amulets and scarabs. It is an opaque variety of chalcedony.

Field identification & locations

Identify in the field by its opaque nature (it does not transmit light even at the edges), its conchoidal (shell-like) fracture, and its inability to be scratched by a steel knife. Frequently found in riverbeds or gravel deposits across the globe.

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