sedimentary

Red Jasper

Silicon dioxide (SiO2) with iron oxide inclusions

Hardness: 6.5-7 on Mohs scale; Color: Brick red to deep terracotta; Luster: Dull to vitreous; Crystal structure: Hexagonal (microcrystalline/cryptocrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Brick red to deep terracotta
Luster: Dull to vitreous

Identified April 6, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica from hydrothermal solutions or within volcanic and sedimentary rocks. The red color is caused by the inclusion of hematite (iron) during the silicification process.

Uses & applications

Commonly used as a gemstone for jewelry (cabochons, beads), decorative carvings, spiritual/metaphysical practices, and as an ornamental stone in polished mosaics.

Geological facts

Jasper is an opaque variety of chalcedony. It has been used since antiquity; ancient Egyptians used red jasper to create amulets associated with the blood of Isis. It is often found in large chunks or boulders rather than as individual crystals.

Field identification & locations

Identify by its opaque red color, smooth waxy feel when polished, and conchoidal (shell-like) fracture edges. It can be found worldwide, with major deposits in India, Russia, Brazil, and the USA.

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