sedimentary
Favosites Fossil (Honeycomb Coral)
Favosites sp. (Extinct genus of tabulate coral)
Hardness: 3-4 (Calcite-based), Color: Gray to tan host rock with white or cream skeletal structures, Luster: Dull to earthy when dry, waxy when wet, Crystal Structure: Hexagonal or polygonal corallites visible in cross-section.
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Physical properties
Hardness: 3-4 (Calcite-based), Color: Gray to tan host rock with white or cream skeletal structures, Luster: Dull to earthy when dry, waxy when wet, Crystal Structure: Hexagonal or polygonal corallites visible in cross-section.
Formation & geological history
Formed during the Silurian to Devonian periods (approx. 419 to 358 million years ago) in warm, shallow marine environments. The fossilized coral was buried in sediment and lithified into limestone or mudstone.
Uses & applications
Primarily used as a geological educational specimen, collector's item, and occasionally polished for use in decorative crafts or lapidary arts.
Geological facts
Favosites are known as 'honeycomb corals' because of the wall-like structures between individual polyps. They played a major role in reef building before their extinction at the end of the Permian period.
Field identification & locations
Identify by looking for a 'honeycomb' or lace-like pattern of small holes or lines on the surface of water-worn pebbles. Commonly found along the shores of the Great Lakes, particularly Lake Michigan and Lake Huron.
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