Fossil or Rock

[Old Bob]

Hi All,

I’m very much an amateur and new to this site / forum. This is my first post. Can anyone please help with identification.

This object was found in the inter tide mud flat region of East Mersey Island, Essex County, England, UK. Cudmore Grove Park beach location.

It appears to have many features resembling bone. There is an inner sponge like area on cross section - possible trabecular structure. The shape has a clear indent groove on the assessed outer surface. My first thoughts were that it could possibly be something like a Patella. Online searching suggests a possible Femur Head part. 

But then that may be my desire to believe.

Can anyone suggest what it may be, and if bone not rock then what could it come from given the location and geology.

Many thanks for any anticipated input.

Regards,

Bob

[goatinformationist]

Oh, maybe a femoral head or condyle?

[Auspex]

It is pretty clearly bone, as shown by the trabecular bone structure in the side view. Just which bone, however, I do not know.

Help can be found with
@Fruitbat or @Harry Pristis