sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Red, brown, and inclusion patterns; Luster: Vitreous to dull; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; SG: 2.58-2.91

Hardness: 6
Color: Red, brown, and inclusion patterns
Luster: Vitreous to dull

Identified May 13, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Red, brown, and inclusion patterns; Luster: Vitreous to dull; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; SG: 2.58-2.91

Formation & geological history

Formed from silica-rich hydrothermal fluids or volcanic ash that percolated through rocks, often accumulating in pockets. This specimen shows brecciated or orbicular-like patterns common in secondary silica deposits.

Uses & applications

Used primarily in lapidary arts for jewelry, decorative objects, and ornamental cabochons. Historically used for seals and tool-making.

Geological facts

Jasper is an opaque variety of chalcedony. The red color is typically due to iron inclusions. Known as the 'supreme nurturer' in metaphysical circles.

Field identification & locations

Identify by its waxy-to-glassy luster when broken, conchoidal fracture, and inability to be scratched by a steel knife. Common in the Western USA, Brazil, and India.