i.g.nova
A thousand leaves
Pyritized endocast (inner mold) of Amaltheus subnodosus ammonite
Early Jurassic (~190 million years old)
Aveyron, France
--
This specimen differs from the others in my collection in that it is an endocast - an inner mold of the creature's shell. Although the shell itself has been lost to time, when the creature fossilized, its flesh was transmuted to pyrite, with enough exquisite fidelity to preserve the details of the shell's inner surface. The leaflike patterns that you see in the foreground are suture lines, which mark the boundaries of each segment of the shell.
More information on the pyritization process can be found here: en.wikipedia.org/wiki/Permineralization#Pyritization
A thousand leaves
Pyritized endocast (inner mold) of Amaltheus subnodosus ammonite
Early Jurassic (~190 million years old)
Aveyron, France
--
This specimen differs from the others in my collection in that it is an endocast - an inner mold of the creature's shell. Although the shell itself has been lost to time, when the creature fossilized, its flesh was transmuted to pyrite, with enough exquisite fidelity to preserve the details of the shell's inner surface. The leaflike patterns that you see in the foreground are suture lines, which mark the boundaries of each segment of the shell.
More information on the pyritization process can be found here: en.wikipedia.org/wiki/Permineralization#Pyritization