sedimentary

Chert (Yellow Jasper)

Cryptocrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Mustard yellow to brownish-yellow; Luster: Waxy to vitreous; Structure: Microcrystalline; Cleavage: None (conchoidal fracture).

Hardness: 6
Color: Mustard yellow to brownish-yellow
Luster: Waxy to vitreous

Identified June 19, 2026More sedimentary →

Explore Chert (Yellow Jasper) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Mustard yellow to brownish-yellow; Luster: Waxy to vitreous; Structure: Microcrystalline; Cleavage: None (conchoidal fracture).

Formation & geological history

Formed from the accumulation of silica-rich microfossils (like radiolarians) or chemical precipitation from groundwater. This specimen appears water-worn or weathered, likely originating from sedimentary beds.

Uses & applications

Historically used for stone tools (lithics) due to its sharp edges when fractured. Modernly used for lapidary work, jewelry, and as landscaping stone.

Geological facts

Yellow jasper is often associated with the solar plexus chakra in metaphysical circles. This specific piece shows signs of percussion flaking, suggesting it might be an anthropogenic lithic flake or tool.

Field identification & locations

Identify by its waxy appearance, smooth conchoidal (shell-like) fractures, and inability to be scratched by a steel nail. Commonly found in riverbeds or limestone deposits globally.