fossil

Fossil Coral

Anthozoa fossil (Calcite / SiO2 replacement)

AI-generated identification · may be incorrect

Hardness: 3 (if calcite) to 7 (if silicified/agateized). Color: Tan, beige, brown, and grey. Luster: Dull to vitreous. Structure: Distinct parallel ridges or corallite septa pattern.

Hardness: 3 (if calcite) to 7 (if silicified/agateized)
Color: Tan, beige, brown, and grey
Luster: Dull to vitreous

Identified July 26, 2026More fossil →

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Physical properties

Hardness: 3 (if calcite) to 7 (if silicified/agateized). Color: Tan, beige, brown, and grey. Luster: Dull to vitreous. Structure: Distinct parallel ridges or corallite septa pattern.

Formation & geological history

Formed in warm, shallow marine waters where ancient coral polyps deposited calcium carbonate skeletons. Over millions of years, the remains were buried and petrified or silicified.

Uses & applications

Used for educational display, lapidary art, jewelry, and paleontology collections.

Geological facts

Corals have existed on Earth for over 400 million years. Some ancient fossil corals, like Petoskey stones, are popular state stones and collector items.

Field identification & locations

Identified by fine parallel or radial ridges indicative of ancient coral wall structures. Commonly found along lake shores, riverbeds, and limestone exposures.