sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Deep reddish-brown to brick red; Luster: Dull to vitreous; Crystal structure: Hexagonal (microcrystalline/cryptocrystalline); Specific gravity: 2.58-2.91.

Hardness: 6
Color: Deep reddish-brown to brick red
Luster: Dull to vitreous

Identified April 23, 2026More sedimentary →

Explore Red Jasper in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Deep reddish-brown to brick red; Luster: Dull to vitreous; Crystal structure: Hexagonal (microcrystalline/cryptocrystalline); Specific gravity: 2.58-2.91.

Formation & geological history

Formed through the infiltration of silica-rich fluids into volcanic or sedimentary deposits. The red color is caused by the high iron content (hematite inclusions) incorporated during the silicification process.

Uses & applications

Predominantly used for lapidary work, jewelry (beads, cabochons), ornamental décor, and as a pocket stone for collectors and enthusiasts.

Geological facts

Red jasper was known in antiquity as the 'stone of endurance' and was often used for seals and talismans in ancient Egypt and Rome. It is a variety of chalcedony.

Field identification & locations

Identify by its opaque red color and high hardness (it cannot be scratched by a steel knife). Look for it in riverbeds or gravel deposits near volcanic regions. Commonly found in South Africa, Brazil, and the USA.