Cadoceras sp. Ammonites
Geological Time: Upper Jurassic , Callovian Stage
Size (25.4mm=1 inch): 61 mm diameter
Fossil Site: Volga River Region, Saratov, Russia
Fossil Code: AA036
Price: $55.00 - sold
 Description:
A large example of an ammonite of the genus Cadoceras of the Callovian
Stage (161 m.y.a) deposits of Russia. This fine example has had one
side of the shell removed to allow you to see the intricate detail
of the interior. You can easily see the individual chambers which
were successively occupied in a spiral pattern by the ammonite as
it grew. The septa (divisions) between the chambers are evident as
the fine line between them. The overall morphology is somewhat different
from other ammonites of the region due to its broader cross-section,
carried through in the different shape to the individual chambers
as well. The environment was anoxic, leading to formation of Iron
Pyrite (Fool's Gold), crystals of which line each chamber for a dramatic
effect. Much of the original shell remains on the exterior, making
for an interesting specimen from either aspect. There is a second,
smaller (18 mm) example which has been attached in the center to allow
you to see what the ammonite's original appearance had been. These
are less frequently seen than the Cosmoceras and Quenstedticeras with
which it shared the Jurassic seas of the region. |
