sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron hydroxides (Goethite)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale), Color: Mustard yellow to golden brown, Luster: Waxy to vitreous, Structure: Microcrystalline/Cryptocrystalline (Hexagonal), Cleavage: None (conchoidal fracture), Specific Gravity: 2.6-2.7

Hardness: 6

Identified March 28, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the deposition of silica-rich fluids in cracks or volcanic ash beds. This specific specimen is an alluvial pebble, shaped and smoothed by river erosion over thousands of years.

Uses & applications

Used primarily in lapidary work for cabochons, beads, and ornamental carvings. Historically used for seals and amulets. Also popular in metaphysical 'gemstone' collections.

Geological facts

Yellow jasper has been a valued gemstone since antiquity, mentioned in ancient literature and used by early civilizations for its durability and bright color. Its yellow hue is caused by inclusions of goethite or limonite.

Field identification & locations

Identify in the field by its opacity (it does not transmit light like agate), its waxy texture when wet, and inability to be scratched by a steel knife. Common in riverbeds and coastal regions globally.