sedimentary

Red Jasper

Silicon Dioxide (SiO2)

Hardness: 6.5-7 (Mohs scale), Color: brick red to brownish Red, Luster: dull to vitreous, Crystal structure: Trigonal (microcrystalline), Cleavage: none, Specific gravity: 2.58-2.91

Hardness: 6

Identified June 19, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: brick red to brownish Red, Luster: dull to vitreous, Crystal structure: Trigonal (microcrystalline), Cleavage: none, Specific gravity: 2.58-2.91

Formation & geological history

Formed when silica-rich fluids permeate through volcanic ash or sediment, often enriched with iron oxides which provide the red color. Typically found in hydrothermal veins or as pebbles in river beds.

Uses & applications

Commonly used for lapidary work, jewelry (cabochons, beads), decorative objects, and as a popular specimen for rock tumbling and metaphysical collections.

Geological facts

Red Jasper has been used since antiquity for seals and amulets. It is believed to have been one of the stones in the breastplate of the High Priest in Biblical times. Its name is derived from the Greek 'iaspis'.

Field identification & locations

Identify by its deep red color, opaque nature, and conchoidal (shell-like) fracture. Look for it in areas with volcanic history or ancient seabed deposits. It will not be scratched by a steel knife.