GuidesMagazineToolsFossilsHunts
Sign up Latest Topics
 
 
 


Reply
  Author   Comment  
crusty_rusty59

Neogene Newbie
Registered:
Posts: 11
Reply with quote  #1 

Fossil found in South Devon today, 10 miles south of Exeter in an open arable field. It is an unusual area to find anything in. But Exeter is surrounded by high ground features.

So, to me it looks like a large kind of Cockle type shell, and underneath shows a black flint.

Happy to accept any advice please, as to what it might be, and also an approximate age.

18br.jpg  18br2.jpg  18bru3.jpg 


0
MicroFossilMan

Cambrian Rockhound
Registered:
Posts: 668
Reply with quote  #2 
Well, when one sees flints in the UK one is inclined to think Cretaceous, say 80-100 million years old. Is the white material in the first image chalk?

It might be a brachiopod or a bivalve ("clam") but the ribs ought to be converging as they get closer to the top of the "shell", and they don't seem to do so. And it is rather large for a UK brachiopod/bivalve. So I'm not quite sure what it is! The keel of an ammonite?

Could you be more precise as to locality? What else was on the field?

__________________
MFM
0
andy333

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 245
Reply with quote  #3 
It looks like a bivalve in flint with the two halves facing you in picture one. There is flint at the top of the Haldon hills and I believe down towards Newton Abbott. It is thought that chalk covered Dartmoor once.
Hope that helps  

__________________
andy333
0
prep01

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 2,711
Reply with quote  #4 
Hi, this is a large fossil but I really need some questions answered please.
1. can you give a more precise location, the more precise the better.
2. was the fossil attached to the flint or was there matrix between them when found. If there was, what was it composed of?
3. Can you please give it a soak in water then a firm but gentle scrub with a toothbrush to remove any loose material then photograph it again from as many angles as possible again with the ruler.

__________________
Colin Huller
0
Richard Cox
Reply with quote  #5 
Bivalve - Plagiostoma
0
crusty_rusty59

Neogene Newbie
Registered:
Posts: 11
Reply with quote  #6 

Thanks all. I hoped it wouldn't be so debatable. Sorry.

Gentle scrub already done. Fossil does seem to be attached to the flint, or at least sat on top of it. Some of the whiteness on top appears to resemble chalk. It scratches white on my finger nail.
There are a few more bits of flint and other stones in the same location, but it is mostly just an arable field. Soil is mostly sandy / muddy.

Could it be a leaf, d'you reckon?

 

x.png 

 

 


0
Brittle Star

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 590
Reply with quote  #7 
Hi,

As flint is marine probably not a leaf. You do get plants in some marine deposits if the environment was near to land.
Do not worry we like debatable items.

__________________
JW

 Never ask a star fish for directions
0
Richard

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 385
Reply with quote  #8 
Bivalve 
Plagiostoma sp. 

__________________
Richard
0
TqB

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 2,486
Reply with quote  #9 
Quote:
Originally Posted by Richard
Bivalve 
Plagiostoma sp. 


That looks right. P. marrotianum gets to that sort of size.

__________________
Tarquin
0
crusty_rusty59

Neogene Newbie
Registered:
Posts: 11
Reply with quote  #10 

Found another fossil today, in a close proximity to the previous Bivalve, Plagiostoma sp. that I posted

I recognise this one already, as have found a few before. Although these have been 30 miles away, and closer to Charmouth.

So I'll say it's a Micraster Urchin, which people on here have previously dated at 65 -85 million years old.
It is flint, and not in the best of condition.

Someone said to me today that farmers may have shipped in sand to improve the local soil structure.
So I imagine this could make any specific ageing rather difficult.
Anyway, what d'you think?

I was delighted to find something I actually recognised, and will be passing the find on to a budding local paleontologist, who is as keen as they they
come.
18oct-pwd2.jpg  18oct_pwd.jpg 

 


0
prep01

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 2,711
Reply with quote  #11 
Yes it's an Echinoderm but I wouldn't be able to give a genus - not enough of the fossil left to say I'm afraid. Please add a scale to all photos though!
__________________
Colin Huller
0
crusty_rusty59

Neogene Newbie
Registered:
Posts: 11
Reply with quote  #12 
Sorry Colin. I keep forgetting the ruler bit. pwd2.jpg 
0
prep01

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 2,711
Reply with quote  #13 
Thanks for the scale bar but as I said - not enough left to ID! Keep looking.
__________________
Colin Huller
0
Chalkers

Cambrian Rockhound
Registered:
Posts: 49
Reply with quote  #14 
I personally think the first fossil is actually banded flint (so commonly mistaken for fossil remains). Do a search online for banded flint and you'll see how easily it can resemble the ribs of bivalves among other creatures.
When shells are preserved in flint the calcite shell is often preserved within it. With erosion and weathering the shell material will break away leaving behind an impression on the flint surface. I cannot tell from the photo, but I can't see any calcite material at the edges where the 'shell' disappears beneath the flint nodule.

The second fossil however is certainly an irregular echinoid; great find! I'm not sure I'd feel comfortable assigning a genus but it looks like it could be a member of the order Holasteroida that includes the genus Holaster, Sternotaxis and Echinocorys. The bulbous protrusion at one end of the fossil could be the periproct (anus) where flint has grown out of the hole (I have a few like this). I'm not too familiar with the South West chalk province but Echinocorys echinoids are the most abundant in my experience in the South east. The size and shape has me edging more towards one of the other two, but like I say I wouldn't feel comfortable saying.
0
prep01

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 2,711
Reply with quote  #15 
Hello Chalkers, these are all photos of ONE fossil, the top, underside and top with scale. Internal flint cast bronen horizontally about halfway up, the top clearly showing the umbulacral pores.
__________________
Colin Huller
0
Brittle Star

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 590
Reply with quote  #16 
Hi Colin

I think Chalmers is referring to the initial post 10 days ago, saying it is banded flint even though the ridges do not go through the flint and where it has flaked off is clearly shown.

__________________
JW

 Never ask a star fish for directions
0
ThomasM

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 765
Reply with quote  #17 
Yeah I also think the top one is banded flint. See the way the ridges fade out and start to get irregular as they blend into the flint (top left, centre bottom). 
__________________
Thomas

If you don't look, you won't find.
0
prep01

Avatar / Picture

Cambrian Rockhound
Registered:
Posts: 2,711
Reply with quote  #18 
Ah! Sorry Chalkers, I hadn't scrolled right to the top of the original #1 post. I see what you are talking about now, but I am 99% certain that it isn't banded flint - the riges are too close and well defined. I still say partial bivalve or brachiopod.
__________________
Colin Huller
0
Previous Topic | Next Topic
Print
Reply

Quick Navigation:

Easily create a Forum Website with Website Toolbox.



Discussions on fossils, fossil hunting, rocks, locations, and identifying your finds.
(C)opyright 2018 - UKGE Ltd and UK Fossils - Contact us