sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

AI-generated identification · may be incorrect

Hardness: 6.5–7 (Mohs scale); Color: Deep brick red to brownish-red; Luster: Vitreous to waxy (especially when polished); Crystal Structure: Hexagonal (trigonal) microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.58–2.91

Hardness: 6
Color: Deep brick red to brownish-red
Luster: Vitreous to waxy (especially when polished)

Identified March 25, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of silica-rich micro-organisms or volcanic ash within sedimentary environments. The red pigmentation is caused by iron (hematite) inclusions that diffused through the silica during diagenesis or hydrothermal activity.

Uses & applications

Used primarily in lapidary work for cabochons, beads, and tumbled stones. Historically used for seal stones, ornaments, and inlay work. Valued in metaphysical circles as a grounding stone.

Geological facts

Jasper was a favorite gem in the ancient world, mentioned in biblical texts and used by Ancient Egyptians for amulets. It is an opaque variety of chalcedony, meaning light does not pass through it even on thin edges.

Field identification & locations

Identify in the field by its opaque nature (unlike translucent carnelian), its high hardness (it will scratch glass), and its distinctive dull, earthy luster on raw surfaces. Commonly found in riverbeds or as nodules in volcanic rock in regions like Brazil, India, and the United States (Southwest and Pacific Northwest).