sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

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

Hardness: 6
Color: Brick red to deep orange-red
Luster: Dull to vitreous

Identified April 1, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica from water-rich environments or hydrothermal fluids, often filling cracks or voids in volcanic rocks or forming as sedimentary nodules. Its red color is derived from high concentrations of hematite (iron) trapped during formation.

Uses & applications

Commonly used for lapidary work, jewelry (cabochons and beads), ornamental carvings, and as a decorative stone in landscaping. Historically used for making tools and seals.

Geological facts

Jasper has been used by ancient civilizations for millennia; the Minoans used it for seals, and it is mentioned in ancient texts as a stone of protection and endurance.

Field identification & locations

Identify in the field by its opaque nature, smooth conchoidal fracture, and inability to be scratched by a steel knife. It is frequently found in gravel beds or near volcanic sites in regions like the Western United States, South Africa, and India.

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