fossil

Coral Fossil

Scleractinia (Class Anthozoa)

Hardness: 3-4 (Mohs scale); Color: Cream, white, or light tan; Luster: Dull/earthy; Crystal Structure: Orthorhombic (Aragonite) or Hexagonal (Calcite replacement); Features visible corallite septa (rib-like structures).

Hardness: 3-4 (Mohs scale)
Color: Cream, white, or light tan
Luster: Dull/earthy

Identified July 15, 2026More fossil →

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Physical properties

Formation & geological history

Formed from the calcium carbonate skeletons of marine polyps. Through time, these structures are buried under sediment and undergo permineralization or recrystallization into calcite. Ages range from the Ordovician to the present.

Uses & applications

Scientific study, educational specimens, home decor, and lapidary use (certain types like Agatized Coral are used in jewelry).

Geological facts

Corals are colonial organisms. Their fossilized remains provide critical information about ancient sea levels, water temperatures, and the movement of tectonic plates.

Field identification & locations

Identify in the field by looking for distinct radial, honeycomb, or chain-like geometric patterns on the surface of calcareous rocks. Commonly found in limestone outcrops or near coastal regions.