sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Hardness of 6.5 to 7 on the Mohs scale, colors vary widely including red, brown, yellow, and green due to iron impurities, luster is vitreous to dull, crystal structure is trigonal (microcrystalline/cryptocrystalline), cleavage is absent (conchoidal fracture), specific gravity is 2.58 to 2.91.

Identified July 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Forms from the silica-rich precipitation in marine environments or hydrothermal solutions, often originating from siliceous oozes or chemical precipitates in sedimentary basins, with ages ranging from Precambrian to recent geological times.

Uses & applications

Used extensively for ornamental objects, cabochons, carved gemstones, polished spheres, and decorative landscaping stone.

Geological facts

Jasper has been utilized since ancient times for talismans, seals, and jewelry. The name derives from the ancient Greek word iaspis, meaning spotted or speckled stone.

Field identification & locations

Can be identified in the field by its opacity, conchoidal fracture, lack of visible crystal grains, and hardness that easily scratches glass. Found worldwide, particularly in regions with ancient volcanic or sedimentary activity such as India, Russia, Brazil, and the United States.