I think they are Miocene too. They look the same as those from Calvert Cliffs MD and identified as Astrhelia palmata. I think the only reason why we didn't find some at Calvert Cliffs this fall is they are buried under the sand. The consensus is there is too much sand deposited on our beaches - bad for both detecting and for fossil hunting larger fossils. Some good fossil ID sheets can be found at TheFossilGuy's site: https://www.fossilguy.com/id_papers/index.htm
If I can find my waterproof rag paper, I'll try to print some of these ID sheets and we can bring them with us in the field when conditions improve.
Visitors to the area should stop by the Calvert Marine Museum. The fossil exhibits are exceptional and well interpreted. They have some good fossil photos here: Invertebrate Fossils | Calvert Marine Museum, MD - Official Website
The coral photo is close to the end of the invertebrate pics.