sedimentary

Red Jasper

Silicon Dioxide (SiO2) - Opaque microcrystalline quartz

Hardness: 6.5–7 on Mohs scale; Color: Red due to iron inclusions; Luster: Dull to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58–2.91

Hardness: 6
Color: Red due to iron inclusions
Luster: Dull to vitreous

Identified March 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the deposition of silica from water (hydrothermal) or in volcanic environments where mineral-rich fluids infiltrate cracks and cavities. It often forms in the presence of iron oxide, which provides the red pigment.

Uses & applications

Commonly used in lapidary work for cabochons, beads, and carvings. Industrially used as an ornamental stone in architecture and historically used for stone tools due to its conchoidal fracture.

Geological facts

Red Jasper has been used since ancient times; in Ancient Egypt, it was often carved into protective amulets and associated with the blood of Isis. It is also mentioned in the Bible as one of the stones in the High Priest's Breastplate.

Field identification & locations

Identify in the field by its opaque deep red color, smooth waxy feel when wet, and sharp, shell-like (conchoidal) edges when broken. It cannot be scratched by a steel knife. Found globally, with significant deposits in India, Brazil, and the USA (Southwest).

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