$Chert (likely a small flake) (Microcrystalline quartz (SiO₂); the flake-like shape alone does not establish whether it is naturally fractured or worked) — sedimentary$

sedimentary

Chert (likely a small flake)

Microcrystalline quartz (SiO₂); the flake-like shape alone does not establish whether it is naturally fractured or worked

AI-generated identification · may be incorrect

Opaque tan-brown with a dull to slightly waxy surface and irregular, sharp edges. Chert is typically Mohs 6.5–7, with a fine-grained, non-cleavable structure and conchoidal fracture; hardness and luster cannot be confirmed from the image.

Identified September 30, 2026More sedimentary →

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At a glance

Common name: Chert (likely a small flake)
Scientific name: Microcrystalline quartz (SiO₂); the flake-like shape alone does not establish whether it is naturally fractured or worked
Category: sedimentary
Identified: September 30, 2026
Method: Standard

AI Estimated Value

About $0–$5 for a small, common unverified fragment; value may differ if it is demonstrably an artifact or an unusual specimen.

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

Forms when silica accumulates and hardens in sedimentary settings, often as nodules in limestone or chalk. Its age and exact formation environment cannot be determined from the photograph.

Uses & applications

Chert has been used for tools and construction aggregate; suitable material may be collected or cut for decorative pieces.

Geological facts

Its conchoidal fracture can produce very sharp edges, making chert important in prehistoric toolmaking.

Field identification & locations

Look for a uniformly fine texture, no visible grains, and curved fracture surfaces; a fresh edge may be sharper and more diagnostic. Chert occurs worldwide in sedimentary rocks, but this small specimen’s locality is unknown.