sedimentary

Flint (chert)

Microcrystalline quartz, SiO₂

AI-generated identification · may be incorrect

Cream-to-tan, opaque to slightly translucent, with a waxy luster and conchoidal fracture; Mohs hardness about 7. The specimen appears to be a chipped fragment with a weathered outer surface.

Identified October 10, 2026More sedimentary →

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Physical properties

Cream-to-tan, opaque to slightly translucent, with a waxy luster and conchoidal fracture; Mohs hardness about 7. The specimen appears to be a chipped fragment with a weathered outer surface.

Formation & geological history

Chert forms when silica accumulates and recrystallizes in sedimentary settings, often as nodules in limestone or chalk. Its age cannot be determined from the image; chert occurs in rocks of many geological ages.

Uses & applications

Historically used for stone tools and fire-starting; today collected or used decoratively. This small rough piece has little commercial value.

Geological facts

Flint is a variety of chert; sharp conchoidal edges made it useful for cutting tools before metalworking.

Field identification & locations

Look for hardness near 7, a smooth curved fracture, and no visible grains; it commonly occurs in chalk and limestone regions. The pale color and shape are consistent with flint, though visual identification alone is not definitive.