sedimentary
Fossil Coral
Scleractinia (fossilized calcium carbonate)
Hardness: 3-4 (Mohs), Color: White, cream, or light tan, Luster: Dull to earthy, Texture: Highly porous with visible septa/pores (corallites), Specific Gravity: ~2.6-2.7
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Physical properties
Hardness: 3-4 (Mohs), Color: White, cream, or light tan, Luster: Dull to earthy, Texture: Highly porous with visible septa/pores (corallites), Specific Gravity: ~2.6-2.7
Formation & geological history
Formed through the fossilization of marine coral colonies. Over geologic time, the original calcium carbonate (aragonite) of the coral can be replaced by calcite or silica. Typical ages range from the Paleozoic to the Cenozoic eras.
Uses & applications
Used for architectural stone, jewelry (agateized coral), aquarium decor, coastal construction, and as geological teaching specimens.
Geological facts
This specimen specifically resembles a 'Honeycomb Coral' (Favosites) or a water-worn Scleractinian coral. Fossil corals represent ancient reef systems that are now high above sea level due to tectonic shifts.
Field identification & locations
Identify by looking for the repeating geometric or floral-like cell patterns (corallites) that differentiate it from porous volcanic rock. Commonly found on beaches near former reef sites or in inland limestone quarries.
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