sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Hardness of 6.5-7 on the Mohs scale, red to reddish-brown color due to iron oxide inclusions, waxy to dull luster, cryptocrystalline structure with conchoidal fracture, specific gravity of 2.58-2.91.

Identified August 5, 2026More sedimentary →

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Physical properties

Hardness of 6.5-7 on the Mohs scale, red to reddish-brown color due to iron oxide inclusions, waxy to dull luster, cryptocrystalline structure with conchoidal fracture, specific gravity of 2.58-2.91.

Formation & geological history

Formed through the precipitation of silica-rich fluids in sedimentary environments or hydrothermal settings, often associated with ancient marine deposits and volcanic activity over millions of years.

Uses & applications

Commonly used for ornamental carvings, cabochons, tumbled stones, jewelry, and lapidary art.

Geological facts

Red jasper has been used since ancient times for talismans, seals, and jewelry by ancient civilizations including the Egyptians, Greeks, and Romans.

Field identification & locations

Identified by its opaque appearance, smooth water-worn texture in riverbeds, conchoidal fracture, and inability to be scratched by a steel knife. Frequently found in stream beds, gravel bars, and ancient marine deposits worldwide.