I got this at a auction a while back not sure what it is help id?

[Kingofthekats]

[izak_]

How much did you pay for it? 

I hope not much, because thats a piece of rock, not a fossil! D:

[ynot]

Not a fossil.

[DevonianDigger]

Yeahh... I was watching this thread. I'm not really a vert guy, so I didn't want to be the first to respond in case I was wrong, but I was pretty sure that this was a suggestive rock. :/

[Kingofthekats]

Not really anything it came with other rocks like 3 dollars

[abyssunder]

The green surface suggests that it was the part exposed to the direct sunlight for the organisms necessitating the photosynthesis on the surface. It could be a gallery of fossil burrows like Thalassinoides or similar ichnogenus in worn condition, or maybe a sponge(?). Hard to tell.

[jewelonly]

Could you take a close, crisp image of the section outlined below, please? I can't tell if I am seeing shells or not. Thank you.  

 

[DevonianDigger]

2 minutes ago, jewelonly said:

Could you take a close, crisp image of the section outlined below, please? I can't tell if I am seeing shells or not. Thank you.  

 

 

Good eyes! I didn't see those features. Definitely some kind of little tube there.

[Kingofthekats]

[jewelonly]

I think you have a limestone rock that still has some tiny fossils or fossil traces evident in it. I am looking just to the right of the knobby area (blurred background in the pic). What do you see? Does it look like some type of small round shell or crinoid? Also, the hole area on the knobby part seems to have faint ridges inside. Do you see them or is it my imagination? No wonder your rock has weathered to this interesting shape.  

[izak_]

I didn't see them either! Thanks for pointing those out

I agree with jewelonly 

[Kingofthekats]

[DevonianDigger]

There's that little guy. It's settled. It's a concretion of fossilized macaroni noodles! (Obviously I'm kidding.) Looks like some type of worm tube to me. There's some other really tiny ones in association as well it seems.

[jewelonly]

Now that very clearly looks like some kind of tube!  

[jewelonly]

Yes, @DevonianDigger, this little rock is becoming more of a mystery. We need the experts now.  

 

Leah

[Kingofthekats]

Here some others

[ynot]

Without an in hand examination it is hard to say if it is fossil or mineral structures.

[Kingofthekats]

[DevonianDigger]

I'm not the person who can give you an exact species on this one, but my vote on those is definitely calcareous worm tubes. They look reminiscent of Pomatoceros.

[jewelonly]

1 hour ago, abyssunder said:

The green surface suggests that it was the part exposed to the direct sunlight for the organisms necessitating the photosynthesis on the surface. It could be a gallery of fossil burrows like Thalassinoides or similar ichnogenus in worn condition, or maybe a sponge(?). Hard to tell.

Thank you for the extra pics, @Kingofthekats. They are very clear and helpful!  

There appear to be multiple tubes or burrows, supporting something like@abyssunder's reply, and yours as well @DevonianDigger.    

Leah

[Kingofthekats]

Thank you for helping me

[DevonianDigger]

Happy to help! A little surprised more people haven't chimed in to give their thoughts yet. Someone will come along and put this one to rest I'm sure! Hang in there!

[jewelonly]

My pleasure @Kingofthekats! I love a good mystery!!  

[abyssunder]

The little sinuous things are calcareous tube worms, similar to the ones below from the Maastrichtian of Netherlands and Belgium.