![]() ![]() Click on the links below and own your very own ammonite fossil evidence for evolution. These ammonite fossils first appeared in the Devonian, and went extinct with the Dinosaurs toward the end of the Cretaceous Period (65 million years ago). Grading of ammolite if largely based on the number and intensity of colours visible, with lower grade material being comparatively dull with less dominant colours. Most people don't realize that Ammonite (Mesozoic cephalopod), is a close relative to the squid. Red and green are fairly common, whilst, blue or purple are rare due to the latter's fragility. Ammolite “opalisation” is a term used to express the similarity between the two minerals due to the spectrum of colours it displays. Additionally – other trace elements have been reported such as aluminium barium chromium copper iron magnesium manganese strontium titanium and vanadium. The chemical composition of ammolite is highly variable, and apart from aragonite it may also include calcite, silica, pyrite, or other minerals. Ammolite was officially recognised as gemstone species in 1981. Other more commonly known biogenic gemstones include amber and pearl. With more than 10,000 species of ammonites known from the fossil record, this group is one of the most characteristic marine fossils of Cretaceous-age rocks. Opening Hours: Monday - Saturday: 10am - 5pm Sunday: 12PM to 5PM. The microstructure of the mineral is inherited from the shell. Explore our beautiful collection of ammolite fossils. They are cephalopods and first appeared in the seas. Ammolite is made of the fossilized shells of ammonites, which in turn are composed primarily of aragonite. Ammonite is a name that comes from the Greek ram-horned God called Ammon are the most widely known fossil. Ammolite is an opal-like organic gemstone found in various placed in the North America and Madagascar. In the mineral and gem worlds the term ammolite is the trade name for the iridescent, nacreous layer of the shell of fossilized ammonite. Ammonites first appeared in the fossil record during the Devonian period some 400 Million years ago, and went extinct at the same time as the dinosaurs at the end of the Mesozoic. Ammonites were squid-like creatures with sharp, beak-like jaws which had a wide range of shell morphologies (as show in the below image). ![]()
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