Details
The 5¼ inch Placenticeras interclare from the upper Cretaceous, Bearpaw formation (75-72 million years ago), with well preserved horns, the whole specimen showing strong iridescences of red, orange, green, with purple to the outer chamber, placed in matrix.

13 x 11 x 1in. (33 x 28 x 2cm.)


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Please note this lot is the property of a consumer. See H1 of the Conditions of Sale.
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Lot Essay

The opal like iridescence of these ammonites from Alberta, Canada has been termed ammolite and since 1981 has had the status of a gemstone. The shimmering, metallic colours were caused by the combination of millions of years of compression and the mineralization of iron, copper and silica which precipitated from volcanic ash. The opalescent layers of colour are particularly prized in the Chinese philosophical system of Feng-Shui.

The ammonites are a group of molluscs that lived in the seas from the mid-Devonian (approximately 400 million years ago) to the end of the Cretaceous (65 million years ago). The sequence of events that famously killed off the dinosaurs also drove the ammonites to extinction.
Post Lot Text
This lot has been imported from outside the EU for sale and placed under the Temporary Admission regime. Import VAT is payable at 5% on the hammer price. VAT at 20% will be added to the buyer’s premium but will not be shown separately on our invoice.

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