sedimentary

Jasper

Microcrystalline Quartz (SiO2)

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

Hardness: 6
Color: Brown, red, yellow, green, or multicolored
Luster: Vitreous to dull

Identified July 30, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the silification of sedimentary or volcanic rocks where silica-rich fluids replace original material or precipitate in cavities. Ages vary widely from Precambrian to Cenozoic.

Uses & applications

Used in ornamental carvings, cabochons, jewelry, lapidary art, and as a collector's specimen.

Geological facts

Jasper has been used since ancient times for seals, signet rings, and weaponry, mentioned in various historical texts such as the Bible and lapidary treatises.

Field identification & locations

Identified by its opaque nature, smooth waxy or dull luster, and conchoidal fracture. Found worldwide in riverbeds, mountainous regions, and sedimentary deposits, highly favored by beachcombers and rockhounds.