sedimentary

Jasper

Silicon dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7.0 (Mohs scale), Color: Red/Brownish-red due to iron inclusions, Luster: Vitreous to waxy, Crystal structure: Hexagonal (microcrystalline quartz), Cleavage: None, Fracture: Conchoidal.

Hardness: 6

Identified April 11, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7.0 (Mohs scale), Color: Red/Brownish-red due to iron inclusions, Luster: Vitreous to waxy, Crystal structure: Hexagonal (microcrystalline quartz), Cleavage: None, Fracture: Conchoidal.

Formation & geological history

Formed from the deposition of silica-rich fluids within volcanic or sedimentary environments. The red pigmentation is typical of iron oxide (hematite) staining of the cryptocrystalline quartz structure.

Uses & applications

Commonly used for lapidary work, jewelry (cabochons), ornamental decoration, and as a semi-precious collector's stone.

Geological facts

Jasper has been used as a gemstone since antiquity. In many cultures, red jasper was believed to have protective properties and was often used in amulets and cylinder seals.

Field identification & locations

Identify by its opacity (unlike translucent carnelian), conchoidal fracture, and inability to be scratched by a steel knife. Commonly found in riverbeds or beaches where silica-rich rocks have undergone tumble-polishing naturally.