sedimentary

Red Jasper

Microcrystalline Quartz (SiO2) with iron oxide inclusions

Hardness: 6.5-7 on the Mohs scale; Color: Deep red, brownish-red; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline/cryptocrystalline); Cleavage: None, exhibits conchoidal fracture; Specific gravity: 2.58-2.91

Hardness: 6
Color: Deep red, brownish-red
Luster: Vitreous to dull

Identified July 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the precipitation of silica-rich fluids in sedimentary environments or hydrothermal veins, often associated with banded iron formations. Geological age varies widely from Precambrian to Cenozoic.

Uses & applications

Used in ornamental carvings, cabochons, jewelry, tumbling, and as a decorative stone.

Geological facts

Red jasper is an opaque variety of chalcedony. The rich red color is primarily due to iron(III) inclusion impurities. It has been used historically by ancient peoples for amulets, seals, and tools.

Field identification & locations

Can be identified in the field by its deep red color, waxy-to-dull luster, conchoidal fracture (creating sharp edges), and inability to be scratched by a steel knife. Found worldwide, particularly in regions with ancient marine or volcanic deposits.

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