sedimentary

Jasper

Silicon dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Red, brown, yellow, or earthy tones; Luster: Dull to vitreous; Crystal Structure: Trigonal/Microcrystalline; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.58-2.91

Hardness: 6
Color: Red, brown, yellow, or earthy tones
Luster: Dull to vitreous

Identified April 12, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the infiltration of silica-rich fluids into volcanic ash or fine sediment. The color is derived from iron impurities. Most specimens are from the Phanerozoic eon.

Uses & applications

Used primarily in lapidary arts, jewelry (cabochons), interior decoration, and as a collector's specimen. Historically used for tools and cylinder seals.

Geological facts

Jasper is an opaque variety of chalcedony. In ancient times, it was called the 'supreme nurturer' and has been used by civilizations including the Minoans on Crete for seals.

Field identification & locations

Identify in the field by its opacity (even when held to light) and smooth, waxy feel after weathering. Commonly found in riverbeds or mountain ranges globally.