sedimentary

Jasper

Silicon Dioxide (Microcrystalline Quartz), SiO2

AI-generated identification · may be incorrect

Hardness of 6.5 to 7 on the Mohs scale, colors typically red, brown, yellow, or green due to iron oxide impurities, waxy to dull luster, cryptocrystalline or microcrystalline structure with conchoidal fracture and no true cleavage, specific gravity of 2.58 to 2.91.

Identified August 5, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the precipitation of silica from aqueous solutions or as a replacement of organic material by silica in sedimentary or volcanic environments, often during periods of hydrothermal activity over millions of years.

Uses & applications

Used primarily for making ornamental objects, polished stones, cabochons for jewelry, and as a collectible lapidary material.

Geological facts

Jasper has been used by ancient civilizations for thousands of years to create tools, seals, and amulets. The reddish varieties derive their color from iron oxide inclusions.

Field identification & locations

Can be identified in the field by its hardness (scratches glass), waxy luster, opaque nature, and smooth water-worn surfaces when found in riverbeds or beaches. Commonly found worldwide.