sedimentary

Worked flint/chert artifact

Microcrystalline quartz (chalcedony), SiO₂; likely a knapped flint or chert flake/core fragment

AI-generated identification · may be incorrect

Hardness about 7 Mohs; opaque gray-beige with tan weathering cortex, dull to slightly waxy luster, and no visible cleavage. The stepped scars, sharp edges, and conchoidal fracture are characteristic of intentional flaking.

Identified August 29, 2026More sedimentary →

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At a glance

Common name: Worked flint/chert artifact
Scientific name: Microcrystalline quartz (chalcedony), SiO₂; likely a knapped flint or chert flake/core fragment
Category: sedimentary
Identified: August 29, 2026
Method: Standard

AI Estimated Value

About $5–$30 as an unprovenienced flint artifact or specimen; authenticated, documented prehistoric artifacts may range from $50 to several hundred dollars, subject to legal restrictions.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Chert/flint formed when silica replaced or concentrated within marine limestone, commonly during the Cretaceous or later; the visible shape was produced by prehistoric knapping. Exact age requires archaeological context and laboratory study.

Uses & applications

As a raw geological specimen it has modest collecting interest; worked pieces were used for cutting, scraping, hunting tools, and fire-starting. It is not typically used as decorative stone in this rough form.

Geological facts

The repeated negative flake scars and impact platforms distinguish a worked artifact from ordinary broken chert. Surface patination can develop after burial and may obscure the original color.

Field identification & locations

Common in archaeological sites and gravel deposits near chert-bearing limestone; identify by conchoidal fractures, sharp margins, percussion bulbs, and organized flake scars. Avoid cleaning or altering it if it may be archaeological.