Unidentified rocks from Big Brook, possible fossils

[Misha]

Went on a trip to Big Brook in August, finds weren't amazing only shells and belemnites and absolutely no teeth but we also found these two rocks that look highly unusual I want to see if these are fossil and if so what they could be.

 

[ynot]

The first piece looks like it could have some plant material in it, better focused pictures would help.

The other piece is non fossil rock, matrix and a mineral vein.

[Fossildude19]

Brightened and cropped: 

 

 

Nothing recognizable, other than to say plant debris.  

Neat looking, though. 

[Max-fossils]

4 hours ago, Misha said:

finds weren't amazing only shells

Shells are amazing! I'd love to see some pictures of them  

[Misha]

3 hours ago, Max-fossils said:

Shells are amazing! I'd love to see some pictures of them  

Here are a few of the oysters we found.

Bottom left is probably my favorite, the color on it is pretty nice.

Edited November 8, 2018 by Misha

[abyssunder]

Another possibility might be trace fossils, burrows like Chondrites or similar, considering their shape, branching character, and the possible origin (marine sediments).
Somehow, it looks like half of a bivalve steinkern with borings / burrows.

 

excerpt from V. Simo & A. Tomasovych. 2013. Trace-fossil assemblages with a new ichnogenus in "spotted" (Fleckenmergel-Fleckenkalk) deposits: a signature of oxygen-limited benthic communities. Geologica Carpathica 64(5): 355-374

[The Jersey Devil]

The smaller one is a rock and the larger is a bivalve steinkern.

[abyssunder]

Now I see your other specimens and almost all of them have nice borings.
The most interesting is the "Y" shaped branching (from the specimen below), which I would assign to Entobia. Sponges use different hard substrates for their diet, shells (like you have), rock pebbles (like the comparative picture), or other hardgrounds with Calcium Carbonate content.

 

comparative picture from here

 

[abyssunder]

8 hours ago, ynot said:

The other piece is non fossil rock, matrix and a mineral vein.

I agree!

[Misha]

2 hours ago, abyssunder said:

Now I see your other specimens and almost all of them have nice borings

Do you know what these could be, found spots like that on many shells.

[abyssunder]

15 hours ago, Misha said:

Do you know what these could be, found spots like that on many shells.

Really nice borings! I'm almost 100% sure that they are Rogerella isp.

[Misha]

4 minutes ago, abyssunder said:

! I'm almost 100% sure that they are Rogerella isp.

Awesome! Thank you for all the help.

[abyssunder]

You're welcome!
Here is an example of Rogerella mathieui.

 

excerpt from R. Breton et al. 2017. Parasitic gastropod bioerosion trace fossil on Cenomanian oysters from Le Mans, France and its ichnologic and taphonomic context. Acta Palaeontologica Polonica 62 (1): 45–57