sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Hardness: 7 on Mohs scale. Color: Brown, yellow, red, and grey mottled patterns. Luster: Vitreous to dull. Crystal structure: Trigonal (microcrystalline/cryptocrystalline). Cleavage: None, exhibits conchoidal fracture. Specific Gravity: 2.58-2.91.

Hardness: 7 on Mohs scale
Color: Brown, yellow, red, and grey mottled patterns
Luster: Vitreous to dull

Identified July 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Forms from the precipitation of silica-rich fluids in sedimentary environments or hydrothermal deposits, often replacing existing carbonate rocks or volcanic ash over millions of years.

Uses & applications

Used in lapidary arts, ornamental carvings, cabochons, jewelry, and as collector specimens.

Geological facts

Jasper has been used since ancient times to create seals, signet rings, and various ornaments. Its diverse patterns are caused by different mineral impurities like iron oxides during formation.

Field identification & locations

Can be identified in the field by its high hardness (scratches glass), waxy to dull luster, and smooth conchoidal fracture showing colorful banding or mottled patterns. Commonly found in riverbeds, gravel bars, and areas of ancient volcanic or hydrothermal activity.