CANADA

Details

AN IRIDESCENT AMMONITE
CANADA
the 10½ inch Placenticeras costatum from the upper Cretaceous, Bearpaw formation (75-72 million years ago), showing strong iridescences of red, orange, green, purple
30 x 23½in. (76 x 61cm.)

Special notice

These lots have been imported from outside the EU for sale using a Temporary Import regime. Import VAT is payable (at 5%) on the Hammer price. VAT is also payable (at 20%) on the buyer’s Premium on a VAT inclusive basis. When a buyer of such a lot has registered an EU address but wishes to export the lot or complete the import into another EU country, he must advise Christie's immediately after the auction. Specified lots (sold and unsold) marked with a filled square not collected from Christie’s by 5.00 pm on the day of the sale will, at our option, be removed to Cadogan Tate. Christie’s will inform you if the lot has been sent offsite. Our removal and storage of the lot is subject to the terms and conditions of storage which can be found at Christies.com/storage. Please call Christie’s Client Service 24 hours in advance to book a collection time at Cadogan Tate Ltd. All collections will be by pre-booked appointment only. Tel: +44 (0)20 7839 9060 Email: cscollectionsuk@christies.com. If the lot remains at Christie’s it will be available for collection on any working day 9.00 am to 5.00 pm. Lots are not available for collection at weekends.

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.

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