Craspedodiscus sp. Ammonite with gorgeous ammolite and pyritized chambers from Volga River, Ulyanovsk Region, Russia
Lower Cretaceous, 201 to 145 myo
Specimen is approximately 11.5" x 13.25" x 2.5"
With included stand specimen measures approx: 11.5" x 14.5" x 6"
Fire Ammonites are fossils that have become coated in an opalescent layer after decades of compression and mineralization, called Ammolite. This superb specimen also has beautiful pyritized chambers. Perfect display piece for your home.
When the ammonite was alive, nacre was the main component of the shell: after the organism’s death, the shell fossilised over time to form aragonite. The ammolite can also contain many other minerals such as calcite and pyrite. Ammolite is not only rare for its vibrant display of colours, but also for the fact that it is biogenic. Most gemstones are not produced by living creatures.
Within the aragonite shell of ammolite, thin platelets are present. When light is shone on an ammolite specimen, light is reflected from these platelet layers and interference occurs. This leads to the vivid spectrum of colour observed in ammolite, usually consisting of red and green hues. Thin platelet layers tend to result in blue and violet shades, whereas thick platelet layers often lead to an iridescent effect mostly consisting of the usual greens and reds.