Madagascan Ammonite Fossil

[Cloud the Dinosaur King]

An ammonite from the Cretaceous of Madagascar, what species?

[Ludwigia]

This is not an ammonite, but rather a Goniatite  These were the predecessors of the ammonites. Your sample comes from the Devonian age and is probably from Morocco, not Madagascar. If you look closely at the second photo, you will see a small imbedded orthocone nautilus on the right, which substantiates my observation. They were long gone before the cretaceous period. Naming a species is practically impossible, since all diagnostic structures have been eradicated through sanding and polishing.                

[Cloud the Dinosaur King]

Just now, Ludwigia said:

This is not an ammonite, but rather a Goniatite  These were the predecessors of the ammonites. Your sample comes from the Devonian age and is probably from Morocco, not Madagascar. If you look closely at the second photo, you will see a small imbedded orthocone nautilus on the right, which substantiates my observation. They were long gone before the cretaceous period.                     

Hmm, very interesting.

[Ludwigia]

Just now, Cloud the Dinosaur King said:

Hmm, very interesting.

I just edited above and added a bit more.

[Aurelius]

Absolutely right, this isn't an ammonite and not from Madagascar. The ammonites from Madagascar do look vaguely similar to the untrained eye, because they are also routinely polished.