sedimentary

Fossilized Coral (Favosites)

Favosites (Extinct Tabulate Coral)

AI-generated identification · may be incorrect

Hardness: 3-4 (calcite) or 6.5-7 (if silicified); Color: Tan, gray, or white; Luster: Dull to earthy; Structure: Honeycomb-like hexagonal cells (corallites).

Hardness: 3-4 (calcite) or 6
Color: Tan, gray, or white
Luster: Dull to earthy

Identified June 19, 2026More sedimentary →

Explore Fossilized Coral (Favosites) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 3-4 (calcite) or 6.5-7 (if silicified); Color: Tan, gray, or white; Luster: Dull to earthy; Structure: Honeycomb-like hexagonal cells (corallites).

Formation & geological history

Formed through the fossilization of ancient marine coral colonies, typically from the Silurian to Devonian periods (approx. 419-358 million years ago).

Uses & applications

Primarily used for geological education, fossil collecting, and occasionally as decorative stones or lapidary material when agatized.

Geological facts

Known as 'Honeycomb Coral' due to the regular pattern of the chambers where individual polyps lived; these corals were reef-builders in ancient shallow seas.

Field identification & locations

Identify by looking for the distinct 'honeycomb' grid pattern on the surface; commonly found in limestone-rich areas like the Great Lakes region or the Ohio River Valley.