sedimentary

Jasper

Silicon dioxide (SiO2) with impurities

Hardness: 6.5-7 (Mohs scale); Color: Yellowish-brown, tan, ochre; Luster: Dull to waxy; Structure: Microcrystalline (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Yellowish-brown, tan, ochre
Luster: Dull to waxy

Identified July 9, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Yellowish-brown, tan, ochre; Luster: Dull to waxy; Structure: Microcrystalline (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Formation & geological history

Formed from silica-rich fluids percolating through sedimentary or volcanic environments, often replacing organic materials or filling cavities. Its age can range from recent to billions of years old.

Uses & applications

Used primarily for lapidary arts, jewelry, cabochons, and as a decorative stone in ornaments and landscaping. Historically used for making tools due to its sharp conchoidal edges.

Geological facts

Jasper is an opaque variety of chalcedony. The yellow-brown color is typically caused by goethite or iron hydroxide inclusions. It has been a popular gemstone since ancient times, mentioned in various mythologies and religious texts.

Field identification & locations

Identify in the field by its opacity (even on thin edges), its hardness (will scratch glass), and its distinctive smooth, shell-like fracture pattern. Commonly found in riverbeds and desert environments globally.