Yellow Jasper
Silicon Dioxide (SiO2) with iron hydroxide impurities
Rock Type: sedimentary

Physical Properties
Hardness: 6.5-7 (Mohs scale); Color: Mustard yellow to golden brown; Luster: Dull to waxy; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Specific gravity: 2.58-2.91
Formation & Geological History
Formed through the infiltration of silica-rich fluids into volcanic ash or fine-grained sediments, often during the Cretaceous or Jurassic periods. The yellow color is caused by the inclusion of goethite or other iron hydroxides.
Uses & Applications
Commonly used in lapidary work, jewelry (cabochons), interior decoration, and as a healing stone in metaphysical practices.
Geological Facts
Yellow Jasper is also known as a 'protection stone' in folklore. Its distinctive mustard-yellow hue distinguishes it from other jaspers which may contain red or green hues.
Field Identification & Locations
Identify by its waxy luster, hardness (it will scratch glass), and opaque appearance. Commonly found in riverbeds or coastal deposits. Key locations include South Africa, India, and the USA (California/Oregon).
Identified on: 5/15/2026
Mode: Standard