A RARE shark s tooth which is at least 55million years old has been discovered in Crow Country. The broken tooth is from an animal that was part of the Orthacodus family, an extinct group of sharks. It was discovered at Barrington quarry, and is the first

A RARE shark's tooth which is at least 55million years old has been discovered in Crow Country.

The broken tooth is from an animal that was part of the Orthacodus family, an extinct group of sharks. It was discovered at Barrington quarry, and is the first of its type to be discovered in the UK or Europe.

It was unearthed by quarry manager John Drayton, who only learnt of its rarity when two scientists arrived at the quarry to do some research.

Mr Drayton, 61, said: "I've got all the things I've found up in my office, including several other sharks' teeth. I didn't realise it was so rare until David Ward and Dr Charlie Underwood visited to do search for prehistoric nodules. They knew immediately that it was very rare and asked whether they could take it up to the Natural History museum with them."

The tooth has now been donated to the museum permanently by the quarry's owners, Cemex.

A spokesman for Cemex said: "Orthacodus first appeared 200 million years ago and lived just after the dinosaurs, outliving them by 10 million years.

"They appear to prefer cool waters and so lived in the northern and southern oceans. Current evidence shows they existed in the areas near Peterborough and on the Dorset coast and now, Cambridge Greensand where Barrington Quarry is situated."

Cambridge Greensand was part of the seabed 90 - 100 million years ago and is a deposit of silty green chalk with phosphate nodules restricted to the Cambridge area.

In the mid 19th century the area was actively quarried for the nodules which were used to make agricultural fertilizer and the green mineral, glauconite, from which the greensand gets its name, was used to dye military uniforms a khaki colour.

It is not the first time Mr Drayton has unearthed a rare fossil. In 2005 he uncovered the remains of an ichthyosaur dinosaur while conducting a routine geological search at the quarry. The bones and teeth are now on display the Natural History Museum.

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