Kosmoceras sp. Ammonite
Geological Time: Jurassic Callovian Stage
Size (25.4 mm = 1 inch): 67 mm diameter matrix: 80 mm by 80 mm.
Fossil Site: Ulyanovsk, Russia
Fossil Code: RA191
Price: $125.00 - sold
 Description:
A magnificent example of the ammonite Kosmoceras sp. of the Callovian
Stage (161 m.y.a) deposits of Russia. Ammonites of this degree of
preservation are difficult to come across. The high degree of preservation
of the natural mother-of-pearl shell makes it appear to be preserved
as fire opal. This is a consequence of light passing through the various
layers of aragonite and conchiolin deposited by the ammonite in life.
This one is quite highly colored, making for a most attractive specimen. |
