State by State
- Specimen Number
Half-boulder of unknown rock, silicified limestone, which slowly fizzes in dilute hydrochloric acid. Close up shows granular texture with irregular horizons, possibly cherty beds or silica replacement horizons.
Sedimentary. Limestone. Silicified.
- Location & Occurrence
Formed on ancient sea floor.
- Geological Age
Likely Early to Mid Paleozoic.
Part of the flat-lying rocks of the platform of the central United States.