sedimentary

Jasper (Red Chert)

Jasper (Silicon Dioxide, SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Deep red to reddish-brown with grayish veins; Luster: Dull to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Deep red to reddish-brown with grayish veins
Luster: Dull to waxy

Identified April 13, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the deposition of microcrystalline quartz or silica-rich volcanic ash. This specific rounded specimen underwent significant water-erosion (river or beach rounding) over thousands of years.

Uses & applications

Commonly used in lapidary work for cabochons, beads, and decorative ornaments. Often used as a pocket stone or for landscaping due to its durability.

Geological facts

Jasper has been used by humans for thousands of years; it was a favorite gem in antiquity, mentioned in many ancient texts for its supposed protective virtues.

Field identification & locations

Identify by its extreme hardness (cannot be scratched by a steel knife) and its smooth, waxy feel when polished by water. Commonly found in riverbeds and along coastlines globally.