sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Hardness: 6.5-7 (Mohs scale); Color: Deep brick red to brownish-red; Luster: Dull to waxy; Crystal Structure: Microcrystalline/Cryptocrystalline (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91.

Hardness: 6
Color: Deep brick red to brownish-red
Luster: Dull to waxy

Identified June 21, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed primarily in sedimentary environments where silica-rich fluids permeate through volcanic ash or sediment. The red color is derived from high concentrations of iron oxide (hematite) during the mineralization process.

Uses & applications

Used extensively in jewelry (cabochons, beads), decorative lapidary work, ornaments, and as a collector's gemstone. Historically used for seals and amulets.

Geological facts

Red Jasper was known as the 'stone of endurance' in ancient cultures and was frequently used by Viking and Germanic warriors to inlay the hilts of their swords for protection and courage.

Field identification & locations

Identify by its characteristic dull red color, heavy weight compared to common rocks, and smooth, shell-like (conchoidal) fracture patterns when broken. Commonly found in riverbeds and desert regions globally, particularly in the Western US, India, and Brazil.

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Cone-in-cone structure (Secondary Sedimentary Structure)

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Clastic Sedimentary Rock Grain (SiO2 dominated)

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Sandstone

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