Mammoths must be one of the most famous of all the extinct animals.
While not having the excitement and glamour of a Dinosaur the size and appearance of them is always very impressive.
I have been selling Mammoth material on Ebay for several years and it is always really popular.

This is a good sized flat piece from the outer coating of a Woolly Mammoth tusk.
From it's size you can guess at how big the full tusk would have been!

The tusk piece measures 17cm long and 6cm across. It is is 5mm thick  

This and many other Mammoth fossils were found in the North Sea between England and Holland.
There was land in this space little more than 6000 years ago so fossils are often dredged up by fisherman in the sea.