Paleozoic Rugose Rugosa Horn Coral Fossil Estate Specimen

This is a fossil Paleozoic era solitary coral known as a Rugose, or Rugosa coral, sometimes called Horn Coral. This specimen is about 4.5 cm at its longest dimensions. It was part of an estate collection with specimens going back to 30 or 40 years. The Rugosa, also called the Tetracoralla, are an extinct order of coral that were abundant in Middle Ordovician to Late Permian seas, roughly between 450 million and 250 million years ago. It is a smaller, but complete specimen, with very nice surface details, and has an unusual cornucopia shape.