sedimentary

Red Jasper (River Polished Quartzite)

Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3) impurities

AI-generated identification · may be incorrect

Hardness: 6.5 - 7 on Mohs scale; Color: Reddish-brown, terracotta; Luster: Waxy to dull (sub-vitreous); Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58 - 2.91

Hardness: 6
Color: Reddish-brown, terracotta
Luster: Waxy to dull (sub-vitreous)

Identified March 24, 2026More sedimentary →

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Physical properties

Hardness: 6.5 - 7 on Mohs scale; Color: Reddish-brown, terracotta; Luster: Waxy to dull (sub-vitreous); Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58 - 2.91

Formation & geological history

Formed from the deposition of silica-rich fluids in volcanic ash or sedimentary beds. The red color comes from high concentrations of iron oxide. This specimen shows signs of mechanical weathering (rounding) likely from river or glacial movement over thousands of years.

Uses & applications

Used primarily in lapidary work for cabochons, beads, and pocket stones. Also used as decorative gravel or in 'metaphysical' retail as a grounding stone.

Geological facts

Jasper was a favorite gem in the ancient world; its name can be traced back in Arabic, Persian, Greek, and Latin. It is an opaque variety of chalcedony that contains up to 20% foreign materials which determine its color.

Field identification & locations

Identify by its opacity (it does not transmit light even on thin edges), its smooth rounded texture from water-tumbling, and its inability to be scratched by a steel knife. Commonly found in riverbeds and gravel pits worldwide.