• Specimen Number

  13

• Description

  Irregular slab of strong reddish brown bedded rock with honeycomb structure and white matrix. Identified by survey staff at the University  of Iowa as a favosite, an extinct, colonial, tabular coral.

• Classification

  Sedimentary. Limestone. Reef. Coral.

• Location & Occurrence

  Marine reef created by extinct form of coral as part of a vast, shallow, epicontinental sea.

• Geological Age

  Devonian.  448-251 Ma (Britannica).

• Geoheritage

  Modern reefs are completely different, dominated by scleractinian corals.

• Links

  Link to State Geological Map from USGS.  Link to Iowa Geological Survey.

• Other

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