sedimentary

Chert (flint) fragment

Microcrystalline quartz (SiO₂), commonly called chert; “flint” is a variety of chert

AI-generated identification · may be incorrect

Hardness about 7 Mohs; pale gray to tan with a waxy-to-dull luster and no visible crystals. Its conchoidal fracture forms curved, sharp edges; specific gravity is about 2.6.

Identified October 4, 2026More sedimentary →

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Physical properties

Hardness about 7 Mohs; pale gray to tan with a waxy-to-dull luster and no visible crystals. Its conchoidal fracture forms curved, sharp edges; specific gravity is about 2.6.

Formation & geological history

Forms when silica precipitates or accumulates and becomes lithified, often in marine sediments; chert occurs across many geological ages. The fragment’s age and exact origin cannot be determined from the image.

Uses & applications

Chert has been used for tools and fire-starting; today it is collected and may be used as aggregate or decorative stone.

Geological facts

Its sharp conchoidal edges made flint valuable for prehistoric cutting tools. The specimen appears to be a naturally fractured fragment, though the image alone cannot confirm its identity.

Field identification & locations

Look for hardness, a smooth waxy surface, and curved fracture surfaces rather than cleavage; chert occurs worldwide in sedimentary formations. Avoid assuming a specific locality without geological context.