sedimentary

Blue-gray flint (chert) fragment

Microcrystalline quartz (SiO₂), commonly called flint or chert

AI-generated identification · may be incorrect

The visible fragment is blue-gray and apparently opaque, with a smooth, possibly conchoidal fracture; quartz has Mohs hardness 7 and a vitreous-to-waxy luster. The image is too limited to confirm its composition or other properties.

Identified October 2, 2026More sedimentary →

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Physical properties

Formation & geological history

Flint forms as silica-rich nodules in sedimentary rocks, often chalk or limestone, through diagenesis. Its age depends on the host formation; no geological age can be determined from the image.

Uses & applications

Flint has historically been used for tools and fire-starting; attractive pieces may be collected or worked into ornaments.

Geological facts

Flint and chert are forms of microcrystalline quartz; “flint” often refers specifically to dark chert associated with chalk.

Field identification & locations

The small pointed piece resembles a chipped stone fragment, but the perforated material around it appears manufactured and does not establish the fragment’s identity. Confirm with hardness, fracture, and a closer view; common flint occurs in chalk and limestone regions.