sedimentary

Jasper (Cream/Yellow variety)

Silicon Dioxide (SiO2) with impurities

Hardness: 6.5-7 (Mohs scale), Color: Cream, beige, pale yellow with dark grey/black mineral inclusions, Luster: Vitreous to waxy, Crystal structure: Microcrystalline (trigonal), Cleavage: None, Specific Gravity: 2.58-2.91

Hardness: 6

Identified March 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the infiltration of silica-rich fluids into volcanic ash or fine-grained sediments. Over millions of years, the silica recrystallizes into chalcedony/jasper. This specimen appears to be water-worn or tumbled, suggesting a fluvial or marine depositional environment before collection.

Uses & applications

Used primarily for lapidary work, cabochons for jewelry, decorative stone, and as a popular 'pocket stone' for collectors and metaphysical practitioners.

Geological facts

Jasper is an opaque variety of chalcedony. The yellow and cream colors are typically caused by inclusions of goethite or iron hydroxides. Its name is derived from the Greek 'iaspis', meaning 'spotted stone'.

Field identification & locations

Identify in the field by its opacity (it will not let light pass through like quartz) and its high hardness (it cannot be scratched by a steel knife). Look for it in riverbeds or coastal areas where harder silicate rocks aggregate.

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