Flake of limestone matrix out of glen rose

[AJinTexas]

Found in Hays county, flaked off of a small cliff on top of a hill.  Not the prettiest of pieces, but the prominent feature in the top right stuck out like a sore thumb (pun intended) and has peaked my interest which won't stop bugging me.  Maybe a steinkern with a flake broken off or 2 that were pressed together and separated? Rudist?  There are some small flakes of shell next to it in the matrix.

 

Left side has some features, but needs some cleaning yet.  The orange material is cemented on and cleaning that off of somewhat flaky limestone is out of my depth at the moment  .  Maybe rudist casts?  The center also has a vein-like structure similar to those found on the left, but a bit larger.

 

 

Reverse side of feature -

 

 

 

Left side shots -

 

 

It can be hard to see in the photos but the tube-structure has a Y in it that continues down and to the left in the photo below -

 

 

Some trace rudist in the bottom center?  Small shell imprint / structure also present / peaking out

 

 

 

 

Let me know your thoughts!  Thanks an advance!