sedimentary

Red Jasper

Silicon dioxide (SiO2) with iron oxide (Fe2O3) inclusions

Hardness: 6.5-7 (Mohs scale), Color: Brick red to brownish-red, Luster: Vitreous to dull (waxy when polished), Crystal Structure: Trigonal (microcrystalline/cryptocrystalline), Cleavage: None (conchoidal fracture), Specific Gravity: 2.58-2.91

Hardness: 6

Identified April 16, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the deposition of silica in fluid-filled cracks or as a result of chemical precipitation in sea water. Its red color is derived from high levels of iron inclusions. It can date back over 3 billion years in old seafloor deposits (Banded Iron Formations).

Uses & applications

Used primarily in lapidary arts for cabochons, beads, and carvings. Historically used for seals and amulets. Also used as decorative stone and for metaphysical collecting.

Geological facts

Jasper is an opaque variety of chalcedony. In ancient times, it was called the 'supreme nurturer.' It was a significant stone in various cultures, including the Egyptians who used it in protective amulets and the Byzantines for mosaics.

Field identification & locations

Identify in the field by its opaque nature (unlike translucent carnelian), its brick-red color, and its inability to be scratched by a steel knife. Commonly found in water-worn pebble form on beaches or in riverbeds globally, notably in India, Brazil, and the USA.

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