Field Museum - This is a 430 million years old Halysites chain coral in a small outcrop of rock along the shore of Lake Michigan in Door County, Wisconsin. The rock is
![chain coral found around Elk Rapids, Mi by us at Nawbin | Rocks and fossils, Fossils, Rock collection chain coral found around Elk Rapids, Mi by us at Nawbin | Rocks and fossils, Fossils, Rock collection](https://i.pinimg.com/originals/74/6f/5d/746f5d52f30d99562c8d2eb3b3612219.jpg)
chain coral found around Elk Rapids, Mi by us at Nawbin | Rocks and fossils, Fossils, Rock collection
![My chain coral fossil (Halysite Coral). I found it in Petoskey, Michigan | Rocks and minerals, Rock and pebbles, Petosky stone My chain coral fossil (Halysite Coral). I found it in Petoskey, Michigan | Rocks and minerals, Rock and pebbles, Petosky stone](https://i.pinimg.com/736x/0f/31/02/0f31024035ab06f52253bf46959b26b3.jpg)
My chain coral fossil (Halysite Coral). I found it in Petoskey, Michigan | Rocks and minerals, Rock and pebbles, Petosky stone
![It's called Halysites or chain coral. It's a species of tabulate coral. Silurian period, from Lake Michigan in NE Illinois | Fossils, Fossil coral, Fossil It's called Halysites or chain coral. It's a species of tabulate coral. Silurian period, from Lake Michigan in NE Illinois | Fossils, Fossil coral, Fossil](https://i.pinimg.com/736x/43/c5/2b/43c52b471f43992c9a332a2a2772b484.jpg)
It's called Halysites or chain coral. It's a species of tabulate coral. Silurian period, from Lake Michigan in NE Illinois | Fossils, Fossil coral, Fossil
![My fossil (and agate) finds from a Lake Michigan beach. I recognize the honeycomb, horn, and chain corals. Trying to figure out what the agatized creature is (left side 2nd down). : My fossil (and agate) finds from a Lake Michigan beach. I recognize the honeycomb, horn, and chain corals. Trying to figure out what the agatized creature is (left side 2nd down). :](https://i.redd.it/jkhoi32x8bc11.jpg)