CANADA

A magnificent example of one of the most spectacular fossils. The unique opal-like iridescence found only on 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, and are rarely seen as vibrantly as on the current example, which unlike many specimens of its size is not composite but is a single shell wonderfully preserved.