Help with ID of piece of tusk/bone/shell ??

[Nbl]

Today along the beach in the Netherlands I found an odd piece of bone?shell?tusk-Enamel? 
This beach is known for prehistoric finds as the sand on the beach was dredged up from the north sea (that in prehistoric times was dry). I found two bone fossils that day as well but this one i can not seem to figure out what it is. The outside has the feeling of a horses hoof to it. Its about 5cm by 3cm

thanks so much for taking a look

[val horn]

Not really sure  i dont see anything i would recognize as enamel,  i guess a piece of bone cortex