Hi, everyone,
(Just a note that this isn't my specimen or photos -- it was posted earlier today on the Fossil Forum facebook group, and my curiosity over what it is has been bothering me all day. The OP found it along the shore of Delaware Bay years ago, he thinks. Not sure whether he was on the Delaware or NJ side)
My guess is that it's a colonial rugose coral like Palaeophyllum, mainly because the longitudinal corallite cross sections in the second photo don't look like heliolitid corallites all packed together, bigger and smaller.
But if it is a rugose coral colony, I wondered whether phaceloid colonial rugose corallites can have coenenchymal tissue among them, or if this is something reserved for helolitids. When this photo is enlarged, it looks like there's coral microstructure in the matrix between and inside the corallites. Is it just typical to see this kind of texture in the matrix of rugose colonies?
Many thanks-- I hope the question makes a bit of sense!
Lisa