fossil

Probable fossil-bearing rock or mineral concretion

Unidentified carbonate-rich concretion with a possible fossil inclusion

AI-generated identification · may be incorrect

Gray, fine-grained material with a rounded central feature and a roughly square, cut or broken exterior. Hardness, mineral composition, and crystal structure cannot be determined reliably from the photo.

Identified September 25, 2026More fossil →

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Physical properties

Formation & geological history

Could have formed as a concretion around fossil or mineral material in sediment; age and exact setting are unknown from the image.

Uses & applications

Primarily of interest for collecting or study; no specific industrial or jewelry use can be identified.

Geological facts

The square outline may reflect cutting or shaping rather than the specimen’s natural form.

Field identification & locations

A visible rounded pattern alone is not enough to confirm a fossil or identify the rock. A closer view of fresh surfaces and tests by a geologist or fossil specialist would help distinguish a fossil, concretion, and other inclusion.