sedimentary

Chert / Flint (Artifact)

Microcrystalline quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale. Color: Brownish-gray with weathering patina. Luster: Waxy to dull. Crystal structure: Cryptocrystalline quartz (chalcedony/chert). Fracture: Conchoidal fracture.

Hardness: 7 on Mohs scale
Color: Brownish-gray with weathering patina
Luster: Waxy to dull

Identified August 3, 2026More sedimentary →

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Physical properties

Hardness: 7 on Mohs scale. Color: Brownish-gray with weathering patina. Luster: Waxy to dull. Crystal structure: Cryptocrystalline quartz (chalcedony/chert). Fracture: Conchoidal fracture.

Formation & geological history

Formed through the chemical precipitation of silica in marine environments (such as chalk or limestone deposits) or biochemical accumulation of siliceous skeletal remains over millions of years.

Uses & applications

Historically used extensively by prehistoric humans to fashion stone tools, arrowheads, spear points, and blades due to its sharp conchoidal fracture properties.

Geological facts

This specimen appears to be a human-crafted lithic artifact (such as a hand axe or biface tool) chipped from sedimentary chert or flint, showing deliberate percussion flaking.

Field identification & locations

Identified in the field by its distinctive conchoidal fracture, hard microcrystalline texture, and evidence of human retouching or flaking along the edges. Found globally near limestone and chalk formations.