sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Hardness: 6.5-7 (Mohs); Color: Red, terracotta, brownish-red; Luster: Dull to vitreous; Crystal Structure: Hexagonal (microcrystalline/cryptocrystalline); Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.58-2.91

Hardness: 6
Color: Red, terracotta, brownish-red
Luster: Dull to vitreous

Identified July 3, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed via the deposition of silica from hydrothermal solutions or volcanic ash, often in sedimentary environments where iron oxides (hematite) permeate the silica to create the red hue. Can be found in Precambrian or younger formations.

Uses & applications

Commonly used for lapidary work, jewelry (cabochons, beads), decorative carvings, and as a popular specimen for rock collectors and metaphysical enthusiasts.

Geological facts

Red Jasper has been used for millennia; it was frequently mentioned in ancient texts and used for seals and amulets in Egypt and Mesopotamia. It is an opaque variety of chalcedony.

Field identification & locations

Identified in the field by its waxy to dull luster, lack of cleavage, smooth conchoidal fractures, and hardness (cannot be scratched by a steel nail). Commonly found in riverbeds and desert environments globally, notably in the USA, India, and Brazil.

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