sedimentary

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)

Hardness: 6.5-7 (Mohs scale); Color: Brick red to deep terracotta; Luster: Dull to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.58-2.91

Hardness: 6
Color: Brick red to deep terracotta
Luster: Dull to vitreous

Identified April 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of silica in volcanic-ash-rich environments or sedimentary deposits where iron impurities permeate the silica, creating the red hue. It often forms in hydrothermal veins or as nodules.

Uses & applications

Used primarily as a gemstone for jewelry, cabochons, and decorative carvings. Historically used for seals and amulets. Also popular in lapidary arts and as a healing stone in alternative medicine.

Geological facts

Jasper has been a favorite gemstone since antiquity; it is mentioned in the Bible and was frequently used in ancient Egyptian and Minoan cultures for jewelry and cylinder seals.

Field identification & locations

Identify by its rich red color, extreme hardness (it will scratch glass and not be scratched by a steel knife), and its smooth, shell-like conchoidal fracture. Found worldwide, with major deposits in India, Russia, Brazil, and the USA (Southwest).

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