sedimentary

Fossiliferous Limestone or Shale

Biomicrite (if limestone) or Fossiliferous Shale

AI-generated identification · may be incorrect

Dark gray to black matrix, fine-grained, hardness 3-4 (if limestone) or variable (if shale), contains embedded fossil fragments.

Identified September 2, 2026More sedimentary →

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Physical properties

Dark gray to black matrix, fine-grained, hardness 3-4 (if limestone) or variable (if shale), contains embedded fossil fragments.

Formation & geological history

Formed in marine environments from the accumulation of mud, silt, and organic debris, typically during the Paleozoic or Mesozoic eras. The embedded fossils indicate a once-thriving marine ecosystem.

Uses & applications

Educational purposes, fossil collecting, and occasionally used in construction or cement manufacture if it's limestone.

Geological facts

This specimen contains visible fossilized remains, possibly brachiopods or crinoid fragments, which are common in Paleozoic marine rocks.

Field identification & locations

Identified by the fine-grained dark matrix with distinct fossil inclusions. Commonly found in areas with exposed sedimentary rock formations. A great piece for amateur fossil hunters.