sedimentary

Chert (Red Jasper variant)

Microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 Mohs; Color: Dull red to pinkish-orange; Luster: Waxy to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.6-2.65

Hardness: 6
Color: Dull red to pinkish-orange
Luster: Waxy to dull

Identified July 20, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 Mohs; Color: Dull red to pinkish-orange; Luster: Waxy to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.6-2.65

Formation & geological history

Formed in sedimentary environments from the accumulation of silica-rich organic remains or chemical precipitation from hydrothermal fluids. This specimen shows signs of stream-wear and iron oxide staining.

Uses & applications

Used historically for stone tools due to its sharp fracture edges. Locally used for lapidary work, jewelry, and as decorative stone or landscaping material.

Geological facts

Red Jasper is a variety of chert colored by iron inclusions. It has been used for thousands of years for seals, beads, and even weapons because it creates razor-sharp edges when flaked.

Field identification & locations

Identify by its waxy luster, smooth conchoidal (shell-like) fracture, and inability to be scratched by a steel knife. Commonly found in riverbeds, gravel pits, and sedimentary outcrops worldwide.