likely coral or sponge found loose on beach, Jutland, Denmark

[anonaddict]

Unidentified presumed coral or sponge,  found loose on beach near Aarhus  9/7/2024.

All units are metric

 

I'm particularly interested to hear from anyone who might know anything about the species.

 

 

[TqB]

It's a sponge, seems to be in Upper Cretaceous flint. The last photo shows a resemblance to the exterior of Ventriculites or similar.

[anonaddict]

thank you for the reply id never have found that out on my own

 

i was initially unsure  about the ID since the fossil sponges ive seen previously are all very regular but after looking at some photos of ventriculites it looks like a likely match but i have a couple followup questions

 

is the white material the internal structure then? so it would have been concealed entirely by the flint if the entire thing had been perfectly preserved? i think i just went down the wrong path because i misunderstood it as the branches somehow supporting the white spongy part but upon further inspection it does indeed seem like it could have been inside

 

and could you elaborate what you base your estimate of age of the rock on? is that just based on geographic location or is there a way to tell more accurately when you dont know the exact origins of the rock like you would if you dug it out of a cliff?

 

 

[oyo]

Another way to look at it.
It look like sponges but it are corals. Ahrdorffia.