Huge Iridescent Canadian Ammonite (Ammolite), 20.5"

This particular ammonite has sold - we have several other similar specimens that we can offer, in a range of sizes from about 10 to 25 inches in diameter. We also have wall-hanging specimens embedded in shale matrix. 

We can show you different options in stock over email or arrange a visit at the showroom in Canada.

Contact Us for more information.

This Placenticeras costatum ammonite is a stunning example of the famous iridescent specimens from Canada; its entire shell is preserved with gorgeous ammolite.

Ammolite is a rare, opal-like gemstone found in Alberta's Upper Cretaceous Bearpaw formation, just east of the Rocky Mountains. This piece displays extremely bright colours throughout, including different shades of reds, oranges, yellows, greens and rare blues and purples. Complete specimens, especially with such intense coloration and lustre, are exceedingly rare.

This large specimen measures 20.5 inches / 52 cm and weighs 26.5 lbs / 12 kg

Deposit: Bearpaw Formation

Location: Southern Alberta, Canada 

Age: Late Cretaceous (71 million years old)

Certificate of authenticity included

Ammonites belong to the Mollusca Phylum in a Class known as Cephalopods – “head-footed” creatures such as octopus and squid. They swam in ancient oceans from 400 million years ago, to their extinction, along with the dinosaurs, 65 million years ago.

Ammonites were free floating invertebrates that were attacked by plesiosaurs and mosasaurs, two groups of gigantic marine reptiles. One way that ammonites could avoid an attack was to quickly change their buoyancy levels, zig zagging and sinking rapidly.

These incredible prehistoric animals ranged in size from tiny species only a few centimetres in diameter to the monstrous Cretaceous ammonite, Parapuzosia seppenradensis, which grew to about 3 meters and would probably weigh close to 1500 kilograms!