Sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Hardness: 6.5-7 (Mohs scale), Color: Mustard yellow to golden brown, Luster: Dull to vitreous/waxy, Crystal Structure: Microcrystalline (Trigonal system), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58–2.91

Hardness: 6

Identified April 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the deposition of silica-rich fluids in volcanic ash or fine-grained sediments. Over time, the silica crystallizes into microcrystalline quartz, with the yellow hue usually caused by the presence of goethite or limonite.

Uses & applications

Used primarily in lapidary arts for cabochons, beads, and carvings. Also used as a decorative stone in mosaics and as an ornamental gemstone in silver or gold jewelry.

Geological facts

Jasper is a variety of chalcedony. Yellow Jasper specifically is often associated with sun and earth energy in various cultural traditions and was historically used by indigenous peoples for tools because of its hardness and sharp fracture edges.

Field identification & locations

Identify by its matte, opaque appearance and high hardness (it will scratch glass). Look for it in riverbeds, desert pavements, and regions with significant volcanic history, such as the Western United States or South Africa.

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