It was excavated from the Stainton gravel beds, and i believe it is human. Ive also been to the police, and Dorman museum the police could not help and ime still awaiting a response from dorman museum middlesbrough. I now know this to be a human tibia shaft there are updated posts.
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Please remember the piece of bone in the first two images was excavated over 2 metres into packed and previously undisturbed deposits ive been informed are proberbly 20,000 years +
Sorry forgot to update this old post, the tibia shaft is indeed Human it was identified by an anthropologist on behalf of Cleveland police