sedimentary

Jasper (Iron Oxide Rich)

Silicon Dioxide (SiO2) with Fe2O3 (Hematite/Goethite) inclusions

Hardness: 6.5-7 (Mohs scale); Color: Brown, red, and mustard yellow; Luster: Dull to waxy; Crystal Structure: Microcrystalline/Cryptocrystalline (Trigonal); Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Brown, red, and mustard yellow
Luster: Dull to waxy

Identified April 2, 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 sediment, often associated with hydrothermal activity or banded iron formations. Can date from the Precambrian to Cenozoic eras.

Uses & applications

Used primarily for lapidary work, cabochons for jewelry, decorative carvings, and as a pocket stone for collectors.

Geological facts

The name Jasper comes from the Greek word 'iaspis', meaning 'spotted stone.' Many varieties like 'Ocean Jasper' or 'Picture Jasper' are named for their unique visual patterns created by mineral impurities.

Field identification & locations

Identify in the field by its opacity (it does not transmit light even on thin edges), its hardness (will scratch glass), and its lack of cleavage. Often found in desert environments, riverbeds, or areas with historical volcanic activity.

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