Ammonites

ammonite with rainbow sheen

The ammonites we have for sale have so many remarkable qualities. Each variety and species reads like a travelogue of ancient oceans. Their widespread presence and diversity of speicies make ammonites useful in dating rock layers.

Some of our ammonites have been polished or split in half to reveal the inner chambers filled with an infinite variety of colors, designs and even crystal formations.

The pyritized ammonites that come from eastern Europe and Russia look as if sculpted from silvery minerals aligned along the septa with crystal caverns in between.

The large display ammonites from Morocco are impressive for their shear size and of course the price. They’'re all so wonderful, you may have trouble choosing which to look at first! Click on one of the sub-catagories listed below to find the ammonite for you!



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Ammonites were a type of cephalopod that appeared in the fossil record during the Devonian Era. They are related to squid and octopus. The nautilus is their closest living relative.

Ammonites were one of the most successful animals of all time. As a group they roamed all of the earth's oceans for over 350 million years! During that time they thrived in huge numbers and thousands of different species.

ammonite suture patterns
Suture Patterns
ammonite drawing


Ammonite suture patterns All of these species fall into 3 orders based on the shape of the septa, Goniatitida, Ceretida, and Ammonitida.You can see examples of these 3 septe shapes at the right.

The ammonite shell had sections, with the living animal occupying only the section of the shell closest to the head. As the soft-bodied ammonite got larger, it grew a new shell section and sealed off the old one with a layer called the septa.

The shape of the septa varied from species to species. They grew more complex shapes over time from a smooth curve in the early Paleozoic Era to complexly convoluted in the Jurassic and Cretaceous Periods.

The old sections were connected by a tube called a siphuncle. Using the siphuncle the ammonite could adjust its bouyancy to move higher or lower in the water table. It did this by pumping gases or liquids into the old chambers. Because all ammonites were carnivores this helped them find better hunting grounds. The ammonites became extinct 65 million years ago during the great extinction at the end of the Cretaceous Period.You can learn more about ammonites here