sedimentary

Coral Fossil (Scleractinia)

Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)

AI-generated identification · may be incorrect

Hardness: 3-4 (Mohs scale); Color: White to light tan; Luster: Dull to earthy; Structure: Hexagonal or colonial coralite patterns; Cleavage: None/Fragmental; Specific Gravity: 2.5-2.7

Hardness: 3-4 (Mohs scale)
Color: White to light tan
Luster: Dull to earthy

Identified May 10, 2026More sedimentary →

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Physical properties

Hardness: 3-4 (Mohs scale); Color: White to light tan; Luster: Dull to earthy; Structure: Hexagonal or colonial coralite patterns; Cleavage: None/Fragmental; Specific Gravity: 2.5-2.7

Formation & geological history

Formed through the accumulation and petrification of coral polyps' skeletons in marine environments. Over time, the organic material is replaced or filled with minerals, typically calcite, throughout the Holocene or older geological epochs.

Uses & applications

Used primarily in home decor, jewelry (beads), aquarium landscaping, and as educational specimens for fossil collectors.

Geological facts

These fossils are the remains of ancient reef-building organisms. While they look like rocks, they are the preserved biological architecture of marine animals. Some fossilized corals (like Petoskey stones) are millions of years old.

Field identification & locations

Identify by looking for the distinct 'honeycomb' or star-like patterns of the coralites. Commonly found on beaches in tropical regions or inland where ancient seas once existed. Collectors should look for distinct radial symmetry in each hole.