What is this material?

[Alexander D.G]

Hi everyone,

 

Collected this one quite a few years ago and have always been curious about its odd material and color. It's quite smooth and does not look like any of the other fossils I found there. So i'm curious if anybody knows what this material is and perhaps how it is formed. Any help would be greatly appreciated!

 

 

[Ludwigia]

Those are bits of shell from an ammonite whorl. It would help us if you would follow instructions and tell us where you found it and what the stratigraphy is.

[Alexander D.G]

I found it quite some time ago so i'm not 100% sure but I think it was found on the Jurassic coast in England. I was aware it's part of an ammonite but what im most curious about is what type of material it is since i've never seen this type of mineralisation before.

[TqB]

31 minutes ago, Alexander D.G said:

I found it quite some time ago so i'm not 100% sure but I think it was found on the Jurassic coast in England. I was aware it's part of an ammonite but what im most curious about is what type of material it is since i've never seen this type of mineralisation before.

It's calcite, the recrystallisation/replacement of the original aragonite. I don't know what impurity makes it that colour!

It looks like Black Ven Mudstone (Sinemurian) nodule preservation from the Lyme Regis and Charmouth coast, an Asteroceras maybe..

[Alexander D.G]

Looks like a match! If you google Asteroceras most of the results picture a similar looking ammonite with (as far as I can tell) the same type of material, albeit a bit lighter than mine. Thanks for the help!