sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Hardness: 6.5-7.0 (Mohs); Color: Yellow to mustard-brown with dark dendritic or spotty inclusions; Luster: Vitreous to waxy; Crystal Structure: Hexagonal (Microcrystalline quartz); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Luster: Vitreous to waxy

Identified February 19, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of fine-grained silica in sedimentary environments like hydrothermal veins or volcanic ash beds. The yellow color results from high concentrations of Goethite or Limonite (iron hydroxides) within the silicate structure.

Uses & applications

Commonly used for lapidary work, cabochons, polished river stones, decorative ornaments, and metaphysical jewelry.

Geological facts

Jasper is an opaque variety of chalcedony. The name 'Jasper' is derived from the Greek word 'iaspis', meaning spotted stone. It has been used by ancient civilizations for seals and talismans for over 5000 years.

Field identification & locations

Identify by its opacity (does not let light through even at edges), distinctive earthy yellow hue, and smooth, waxy surface after tumbling. It is often found as rounded cobbles in riverbeds or gravel deposits in volcanic regions.

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