sedimentary

Jasper

Silicon Dioxide (Microcrystalline Quartz, SiO2)

Hardness: 6.5 to 7 on the Mohs scale, Color: Red, brown, yellow, green, or multicolored, Luster: Vitreous to dull, Crystal structure: Trigonal (microcrystalline/cryptocrystalline), Cleavage: None (exhibits conchoidal fracture), Specific Gravity: 2.58 to 2.91

Hardness: 6

Identified July 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from silica-rich fluids precipitating in sedimentary environments or hydrothermal veins, often associated with the alteration of silica-rich volcanic ash or sediments, dating back billions of years across various geological eras.

Uses & applications

Used for ornamental carvings, polished cabochons in jewelry, decorative items, and as a popular specimen for mineral collectors.

Geological facts

Jasper has been used by ancient civilizations since prehistoric times for tools, seals, and amulets. Red jasper gets its distinct color from iron inclusions.

Field identification & locations

Easily identified in the field by its opaque appearance, waxy to dull luster, conchoidal fracture, and resistance to scratching steel (hardness over 6). Found worldwide in sedimentary rock formations and riverbeds.

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