Hi. I went fossil hunting in the summer holidays of last year to Mallorca, and the fossils there are Neogene aged. I showed some of my fossils from this location, like the Brachiopod with worm burrowings, but I've done some research on these pieces and I believe they could be Echinoid spines (?)
Am I right?
I've also showed a picture of some very simular fossils which I found on Google.
Any replies would be really appriciated because I've always wanted to find an Echinoid fossil (although I did find one complete one, but it was stuck in a boulder, but it was quite loose so hopefully it will have eroded and it will come out when I go back next year.)
1. The shape is a bit clubby, reminiscent of that sort of echinoid spine (well represented by the images of Pseudocidaris in the images in the last link). But I am fairly sure it is a piece of sediment containing small corals; the overall shape being insignificant.
2 & 3. Not an echinoid spine; they are never bent (at least not that I've seen). It may be a piece of sedimentary rock representing a burrow. Recently, as a pebble, no.3, appears to have become encrusted with a bryozoan colony.
(4. the same specimens, OK)
Echinoid spines are quite interesting objects in that each one is a single crystal of calcite - a remarkable construction for an animal. They have internal structure not only in terms of their crystallography, but also by way of pores and growth rings. Read more here
Because of their single-crystal structure, echinoid spines never have the sort of feature shown running across your specimen in your first photo.
I wish you luck in your echinoid quest.
No - not coprolite - not with those regular features parallel with each other through it. And the fact that the features on the side are seen in long-section shows that the overall shape is at least partly the result of modern erosion. So the current somewhat-faecal overall shape may be incidental and misleading.
I mean it is a rock that contains corals, and because they are all parallel with each other, I suspect they are part of the same colony. With some coral colonies, individuals stand proud of the colony surface, and when turned to rock, that can cause some of the individuals to appear to be separated from each other by sediment. I think we may see that in your specimen. Have a look at this modern example, and hopefully you will be able to imagine what I am describing:
The prominence of corallites' walls is one of the standard characters used in describing corals, modern and fossil. You can read about it here, eg.
That will give you some more examples of the sort of coral I think you have (look at photos captioned 'prominent').
Hi again Mike and tabfish. Here are two more of the same fossil which I found. I did find one more, but I gave that one to my Grandma.