sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Reddish-brown, dull to earthy; Luster: Vitreous to waxy; Structure: Microcrystalline; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Reddish-brown, dull to earthy
Luster: Vitreous to waxy

Identified July 15, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Reddish-brown, dull to earthy; Luster: Vitreous to waxy; Structure: Microcrystalline; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91

Formation & geological history

Jasper is an opaque variety of chalcedony. It forms when silica-rich fluids permeate through sedimentary or volcanic rocks, often replacing the original material. The red color comes from iron impurities like hematite or goethite. Ages vary from Precambrian to recent.

Uses & applications

Used primarily as a gemstone for jewelry, cabochons, and decorative carvings. Industrially, it has historically been used for creating stone tools due to its hardness and sharp fracture edges.

Geological facts

Jasper has been a favorite gem since antiquity, mentioned in the Bible and worn by ancient Egyptians in amulets. It is often called the 'Supreme Nurturer' in metaphysical circles.

Field identification & locations

Identify by its opaque nature (unlike translucent carnelian), its high hardness, and its reddish-brown streak. Common in riverbeds and desert environments such as the Southwest US, India, and Brazil.