sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

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

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

Identified March 14, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed via the accumulation of silica-rich micro-organisms or volcanic ash within sedimentary environments; the red color comes from iron oxide (hematite) impurities during the mineralization process over millions of years.

Uses & applications

Used primarily in lapidary arts for cabochons, beads, and decorative carvings; historically used for seals, jewelry, and talismans; also popular in metaphysical collections.

Geological facts

Jasper was a favorite gem in the ancient world, referenced in many cultures including Greek and Roman literature; it is considered one of the 'stones of the breastplate' in biblical history.

Field identification & locations

Identify by its opaque nature (it does not transmit light even on thin edges), its characteristic deep red streak, and its high hardness (it will scratch glass). Commonly found in the United States (western states), India, Russia, Brazil, and South Africa.

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