sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with hydrated iron oxide impurities

Hardness: 6.5-7 (Mohs scale); Color: Bright mustard yellow to deep gold; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline/cryptocrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.58–2.91

Hardness: 6
Color: Bright mustard yellow to deep gold
Luster: Vitreous to dull

Identified March 17, 2026More sedimentary →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed through the deposition of silica from volcanic ash or hydrothermal solutions into cracks, often during the Proterozoic to Cenozoic eras. The yellow coloring is due to the presence of goethite or other iron hydroxides during formation.

Uses & applications

Commonly used as a gemstone for lapidary work, cabochons, beads, and ornamental carvings. It is also a popular stone for 'worry stones' or landscaping decoration.

Geological facts

Jasper is an opaque variety of chalcedony. Historically, it was known as the 'Supreme Nurturer' and has been used in cultures worldwide for thousands of years as jewelry and protective amulets.

Field identification & locations

Identify in the field by its opacity (unlike translucent citrine), conchoidal fracture, and inability to be scratched by a steel knife. Frequently found in riverbeds or desert regions in India, Russia, Brazil, and the USA.

Other sedimentary specimens

See all

Sandstone or Siltstone

Arenite (if sandstone)

Sedimentary

Sandstone

Arenite (primarily SiO2)

sedimentary

Shale or Slaty Mudstone

Argillaceous sedimentary rock

sedimentary

Chert Breccia

Brecciated Chert (Microcrystalline Silica)

sedimentary

Sandstone (Quartz-rich)

Arenite (SiO2)

sedimentary

Sandstone (with man-made markings)

Arenite (composed primarily of Quartz, SiO2)

sedimentary