sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Hardness: 6.5-7 (Mohs scale); Color: Brick red to deep terracotta; Luster: Dull to vitreous; Crystal Structure: Microcrystalline/Trigonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91

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

Identified March 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the process of silica-rich fluids permeating volcanic ash or sedimentary rock, often in hydrothermal environments. Its red color is derived from iron (hematite) inclusions incorporated during crystallization over millions of years.

Uses & applications

Widely used in lapidary for cabochons, beads, and carvings. Used in jewelry, as an ornamental stone in interior design, and historically used for stone tools due to its sharp conchoidal fracture.

Geological facts

Jasper has been used as a gemstone for thousands of years; it was mentioned in the Bible and was a favorite in the ancient Babylonian and Egyptian civilizations for seals and amulets. It is an opaque variety of chalcedony.

Field identification & locations

Identify in the field by its opaque deep red color, smooth waxy feel on broken surfaces, and inability to be scratched by a steel knife. Common in the Western USA (Oregon, Idaho, California), India, and Brazil. Collectors should look for unique banding or patterns.

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