sedimentary

Red Jasper (Chert)

Silicon Dioxide (SiO2)

Hardness: 6.5-7 Mohs; Color: Brick red to brownish-red; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Brick red to brownish-red
Luster: Vitreous to dull

Identified May 16, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 Mohs; Color: Brick red to brownish-red; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Formation & geological history

Formed through the accumulation and silicification of microcrystalline quartz, often in hydrothermal veins or as nodules in volcanic rocks and sedimentary bands. Red coloration comes from iron oxide (hematite) inclusions.

Uses & applications

Widely used as a gemstone for jewelry, ornamental carvings, lapidary art, and sometimes as a spiritual or healing stone in alternative practices.

Geological facts

Red Jasper has been used since antiquity; it was mentioned in the Bible as a 'sacred stone' and was commonly used by the ancient Egyptians for amulets and jewelry to symbolize the blood of Isis.

Field identification & locations

Identify in the field by its waxy luster, opacity (unlike translucent carnelian), and smooth, shell-like fracture pattern. Commonly found in riverbeds, deserts, and volcanic regions worldwide, including India, Brazil, and the USA.