sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

Hardness: 6.5–7 on Mohs scale; Color: Terracotta red to brownish-red; Luster: Dull or waxy when raw, vitreous when polished; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58–2.91

Hardness: 6
Color: Terracotta red to brownish-red
Luster: Dull or waxy when raw, vitreous when polished

Identified March 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica from water or volcanic ash. The red color comes from iron oxide (hematite) impurities during the solidification process. These specimens can range from millions to over a billion years old.

Uses & applications

Commonly used in jewelry (cabochons and beads), decorative ornaments, stone carving, and as a popular specimen for rock tumbling and aesthetic collection.

Geological facts

In ancient times, Red Jasper was known as the 'stone of endurance' and was often used in the hilt of swords to protect warriors. It is an opaque form of chalcedony.

Field identification & locations

Identify by its deep red color, hardness (it will scratch glass), and its lack of transparency even on thin edges. Commonly found in South Africa, Brazil, India, and the southwestern United States. Look for smooth, waxy surfaces in riverbeds.

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