sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Hardness (Mohs): 6.5-7; Color: Rusty red to brownish-red; Luster: Dull to waxy; Crystal Structure: Microcrystalline/Cryptocrystalline (Hexagonal/Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Color: Rusty red to brownish-red
Luster: Dull to waxy

Identified July 8, 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, then hardened under pressure. Its red color is derived from high iron content. It can be found in sedimentary beds or as stream/beach pebbles.

Uses & applications

Used primarily as a gemstone for jewelry (cabochons, beads), decorative carvings, and as a popular lapidary material for rock tumbling and polishing.

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 often referred to as a 'stone of endurance' in metaphysical circles.

Field identification & locations

Identify in the field by its deep red color, opacity (it does not transmit light even on thin edges), and its ability to scratch glass. Commonly found in riverbeds and on beaches as water-worn pebbles.

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