sedimentary

Coral Fossil Rock (Syringopora)

Syringopora (Organ-pipe Coral fossil in Limestone matrix)

AI-generated identification · may be incorrect

Hardness: 3-4 (matrix) to 7 (if silicified); Color: Tan, brown, or grey matrix with white or cream tube patterns; Luster: Dull to earthy; Structure: Colonies of parallel or radiating calcareous tubes; Cleavage: None

Hardness: 3-4 (matrix) to 7 (if silicified)
Color: Tan, brown, or grey matrix with white or cream tube patterns
Luster: Dull to earthy

Identified June 29, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed during the Paleozoic era (Silurian to Carboniferous periods), typically 300 to 450 million years ago. They represent ancient shallow marine environments where coral colonies were buried in calcium carbonate-rich sediment.

Uses & applications

Educational specimens, fossil collecting, decorative lapidary work (when polished), and geological research.

Geological facts

Syringopora is known as the 'organ-pipe coral' because its parallel tubes resemble the pipes of a church organ. These corals were important reef-builders hundreds of millions of years ago.

Field identification & locations

Identify in the field by looking for 'pin-hole' or 'spaghetti' patterns on the surface of smooth river stones or limestone outcrops. They are common in the Great Lakes region of North America and limestone-rich mountainous areas.