Both of the below ammonites come from the area around Vöhrum (east of Hannover), Germany from Cretaceous (Aptian stage) rocks. They are striking for their pure white, opalescent shells.
This is Hypacanthoplites jacobi
And this is Leymeriella schrammeni
Thanks to Nils for the specimens!
Very nice, I have similar type of ammonites from Germany but made the mistake of trying to clear the matrix from the center whirl with a needle. It punched right through!
ReplyDeleteWhat type of mineral are the fossils composed of? It almost looks like the chalk form of calcite.
Mike, The exterior shell still has some mother of pearl sheen to it so that doesn't seem to have been affected much by burial. I'm sure there has been some replacement of the shell though with the matrix looking like a chalky mudstone.
DeleteYeah, I've seen some ammonite where the smallest center whorls are missing. Perhaps they were not replaced as well as the rest of the shell?