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Can anyone identify

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

The Delaware Bay and Delaware River shores are littered with lovely marine erratics. They aren't local. They aren't young. You have to dig pretty darn deep in Delaware just to get to the Cretaceous in some places. These are Paleozoic. Many pieces are limestone and probably from the Mahantango FM. But, I find just as many that are definitely not limestone. They are silicified to cert and other shades of SiO2 plus a bit of dark blue/black mineral. I'm thjingking they are ordovician, based on the Foerstiphyllum sp. corals here. The puzzle is, where do they and the other silicified corals, sponges, bryozoa etc, come from? The DE geological Survey doesn't even mention the erratics. I was told that it's been washed down from the Appalachians. Okay, there are definitely ordovician layers there that could have eroded into the river, but all I can find are formations of limestone and fine-to-very-fine grained sandstone. Been doing all kinds of searching through descriptions of geological formations in the area and I'm coming up blank. Anyone have any ideas?

I'm stumped. I've been collecting erratics off the beach along the Delaware Bay for the last six months and I keep coming up with mysteries. This specimen is 1" long. Unfortunately, because it is an erratic, all I can tell you is that rocks of this type wash down from the Appalachians all along the Delaware River and Bay til it reaches the Atlantic Ocean. They are Paleozoic, but I don't know enough of the geology from PA and NJ to narrow it down by rock type to a formation. Can't find a high enough resolution GEO Survey map, either. Other fossils in this type of rock are rugose corals, tabulate corals, bryozoa, and pinhead-sized crinoids, so big possible spread on the time frame. No trilobites yet, unfortunately! I have a small id sheet from the Mahantango Formation and an ID book for the Middle and Upper Devonian of NY, but neither have anything similar. I posted on the FB group and got three people saying it was one of these (yeah, I knew that) but each thought it was a different phylum. Can I get a consensus on phylum, if not a genus here? Can anyone give me links to good reference material for my other mysteries?

The hubbub of the holidays is over. The cold, crisp air has descended here in the Mid-Atlantic. The ground is frozen, but I was craving sunshine and the hunt. With blue skies today and the promise of snow tomorrow, I headed to the one place I was reasonably certain wouldn't be completely frozen -- the Delaware Bay. After all, we put salt on the roads here to keep them from freezing. How cold is it this week? Cold enough to freeze salt water! Here and there, exposed spots dotted the beach and the highest part of the bank, above the high tide line, was still exposed. There were a few pebbles here and there, but the odds of finding something in such scant gravel wasn't promising. I spent the next hour with a friend, exploring the ice formations with cameras. Still, my beloved beach did not disappoint. I found a couple of little favosites corals in the freezing tide pools and a 3-inch chunk of local petrified wood lying along the trash line. There is something ironic about finding petrified - silicified - wood frozen to the beach sand!