Rugose Coral (Horn Coral)
Rugosa cf. Coral • Body fossil, marine invertebrate
Geological Period
Devonian (or Carboniferous)
Estimated Age
359 to 419 million years old
Preservation Type
Silicification and calcitic replacement
Condition Assessment
Fair condition; shows significant weathering, surface abrasion, and partial fragmentation due to post-depositional transport and exposure
Taxonomic Classification
Phylum: Cnidaria, Class: Anthozoa, Order: Rugosa
Morphological Description
Small, weathered colonial or solitary rugose coral fragment displaying prominent septa, internal corallite walls, and a porous, honeycomb-like weathered surface structure.
Rock Matrix
Weathered argillaceous limestone or calcareous shale matrix with minor iron oxide staining
Formation & Location
Found globally in Paleozoic marine sedimentary formations, such as the Jeffersonville Limestone or Columbus Limestone in North America
Size & Dimensions
Approximately 3 cm in maximum length, falling within the smaller end of typical solitary rugose coral fragments
Value & Rarity
Estimated Market Value
$5 to $15
Auction Estimate
$10 to $25
Rarity Assessment
Common
Scientific Significance
Provides evidence of ancient shallow-water tropical marine environments, reef ecology, and Paleozoic benthic community structures
Preparation Recommendations
Gentle washing with water and a soft nylon brush to remove loose dirt. Store in a dry, stable indoor environment.
Notable Features
Exposed internal calice structures and weathered corallite walls showing the distinct structural geometry characteristic of rugose corals