sedimentary

Fossilized Coral

Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)

AI-generated identification · may be incorrect

Hardness: 3-4 (calcite) to 7 (agatized); Color: white, tan, pinkish; Luster: dull to waxy; Structure: distinct honeycomb or septa patterns; Cleavage: none.

Hardness: 3-4 (calcite) to 7 (agatized)
Color: white, tan, pinkish
Luster: dull to waxy

Identified April 17, 2026More sedimentary →

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Physical properties

Hardness: 3-4 (calcite) to 7 (agatized); Color: white, tan, pinkish; Luster: dull to waxy; Structure: distinct honeycomb or septa patterns; Cleavage: none.

Formation & geological history

Formed through the fossilization of marine coral colonies. Over millions of years, the organic coral skeleton is replaced by minerals, often in shallow marine environments during the Paleozoic to Cenozoic eras.

Uses & applications

Used primarily for jewelry (cabochons), ornamental decoration, aquarium decor, and as educational geological specimens.

Geological facts

Agatized coral is the state rock of Florida. These fossils can be hundreds of millions of years old and represent ancient reef systems that are now on dry land due to shifting plates.

Field identification & locations

Identify by looking for repeating geometric 'star' or 'flower' patterns (the corallites) on the surface of a stony rock. Frequently found in coastal regions or areas that were ancient seabeds.