sedimentary

Jasper with Hematite inclusions

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)

Hardness: 6.5-7 (Mohs scale); Color: Yellow-brown, tan, with streaks of crimson red; Luster: Dull to waxy; Crystal structure: Microcrystalline/Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.9

Hardness: 6
Color: Yellow-brown, tan, with streaks of crimson red
Luster: Dull to waxy

Identified April 5, 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. The red coloration is caused by iron oxidation (hematite) during the diagenesis process, often in Precambrian iron-rich environments.

Uses & applications

Used primarily as an ornamental stone, for lapidary work (cabs and carvings), landscaping, and as a collector's specimen. Historically used for making tools due to its sharp fracture edges.

Geological facts

Jasper is an opaque variety of chalcedony. The name comes from the Greek word 'iaspis', meaning 'spotted stone.' Many ancient civilizations believed jasper carried healing powers and protective energy.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel knife), smooth waxy feel on breaks, and opaque nature. Frequently found in river beds or areas with exposed sedimentary or volcanic strata.

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