sedimentary

Jasper

Silicon dioxide (SiO2)

Hardness: 6.5-7 (Mohs scale), Color: Red, brown, yellow, or green, Luster: Vitreous to waxy, Crystal Structure: Microcrystalline quartz, Cleavage: None, Specific Gravity: 2.58-2.91

Hardness: 6

Identified July 1, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: Red, brown, yellow, or green, Luster: Vitreous to waxy, Crystal Structure: Microcrystalline quartz, Cleavage: None, Specific Gravity: 2.58-2.91

Formation & geological history

Formed through the deposition of silica from water into cracks or cavities in other rocks. It is often found in sedimentary environments and can range from ancient Precambrian ages to more recent formations.

Uses & applications

Used primarily in jewelry as a gemstone, for ornamental carvings, and historical decorative art. It is also a popular collector's item due to its variety.

Geological facts

Jasper has been used for millennia; the ancient Egyptians used it for amulets and jewelry. Its name comes from the Greek word 'iaspis', meaning spotted stone.

Field identification & locations

Identify in the field by its opaque nature (unlike translucent chalcedony), smooth waxy feel when polished, and conchoidal fracture. Commonly found in riverbeds, deserts, and volcanic regions globally.