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Opal Desmoceras Ammonite 92mm


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Opalescent Desmocera ammonite excavated in the Mahajanga jungle of Madagascar. The unrivalled tropical island environment, in the Indian Ocean, off the coast of South East Africa. The Island having the most unusual flora and fauna is also blessed with a unique deposit of colourful mineralised fossils. Rich minerals developing in the earths layers have created unequalled depositions of rare fossils, some outcrop and have in recent years have been harvested for there natural beauty. Read the full description below...

Genus: Desmoceras ammonite.
Age: Cretaceous, approximately 120 million years ago.
Origin: Mahajanga Jungle, Madagascar.

Desmoceras ammonite measurements.
Height: 7.91 cm
Width: 9.25 cm
Depth: 3.83 cm

Approximate weight: 0,297 g

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Opalescent Desmoceras ammonite excavated in the Mahajanga jungle of Madagascar. The unique tropical island environment, in the Indian Ocean, off the coast of South East Africa. This Island having the most unusual flora and fauna is also blessed with a unequalled deposit of the colourful fossils. Rich minerals have developed in the earths layers creating unique depositions of plentiful fossils, some outcrop and have in recent years have been harvested for there natural beauty.

Opalescent Desmoceras ammonite excavated in the Mahajanga jungle, Madagascar. Prepared in the laboratory in the UK using the latest technology enabling us to offer our customers the highest quality iridescent Ammonites. Each ammonite has been prepared using micro pneumatic tools, removing the surrounding matrix to the centre, revealing the fine Cleoniceras scientifically and aesthetically. This ammonite displays an attractive array of vivid colours throughout the nacre of the shell flashing bright blue, glaucous greens with strikingly vivid highlights of scarlet red transitions to the keel of the ammonite.

Rare colours found in specimens are maize yellow, amber, blue, glaucous, cerulean, purple, lavender, scarlet red, coral pink and lavender pink. To find the best Cleoniceras specimen for your collection, friend or loved one, you should start looking at the aesthetics. Make sure it is symmetrical, look for flaws on the shells surface, usually these will develop as chips or even filler, large specimens are prone to these anomalies, sometimes these are badly prepared or of a very low grade. Next the colouration, is it vibrant, does it reflect in low light, getting the best out of a fairly dull specimen, angled photographs in dark light using florescent lights can achieve a sellers desired perspective. One needs to see consistency when looking to buy online and make sure the photographer has caught true reflections of light using standard white lights. In our photography no flash is used therefore one can gain a true likeness of how the ammonite displays and will display in your collection.

Ammonites are part of the Ammonitida of marine invertebrates. These were fascinating creatures from the deep oceans and believed to be aggressive creatures like squids today. With extremely large eyes and remarkable vision they could easily hunt on their prey at great depths where little or no light penetrates the deep oceans. The Cephalopod would attain its prey using their long tentacles, prey such as other crustaceans and fish, much as the persisting modern day Nautilus Pompilius which can be found in the Pacific today.

Some cephalopod facts; Off the Great Barrier Reef at depths between 200 to 400 meters, sightings of the Nautilus Pompilius were made, showing the pressures these Cephalopods can attain. The Ammonites fell into decline and began there own extinction around 70 million years ago, preceding a mass extinction event, at the end of the Cretaceous period, around 65 million years, the ammonites were extinct. One of the main differences separating the Nautiloids from the ammonites is a shield like aptychi, plural aptychus, very occasionally found in the living chambers of fossilised ammonites. In fact there are two pairs of shield like covers the aptychus and anaptychus. These look very much like the valve's of a bivalve shell. These aptichus are not found in fossils after the Cretaceous extinction event, yet are found in the fossil ammonites from the Devonian Period, therefore the ammonites completely died out after the Cretaceous KT boundary event. The aptychi were thought to be a cover for the last living chamber. Made of calcite rather than aragonite, the later the substance from which the shell is made. Aptychi have been hotly debated as being either covers for the mandibles of the ammonite or a cover for the last living chamber, the argument is still out on exactly what the use of the aptychi was. Ammonites are important index fossils, it is often possible to link the sediment layer in which they are found to specific geological time periods. The largest ammonite to date is around 2.5 meters in diameter from Germany.

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Additional Information

Age Cretaceous
Origin Madagascar
Colour Opalescent

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