Fossil mammoth tooth. No other information I'm afraid, given to me when I was much younger.
Digitized with Autodesk Remake.
Some attempt to de-light following this guide: https://blog.sketchfab.com/de-lighting-3d-scans-in-unity-by-pete-mcnally/
However, photogrammetried it in two goes (each half seperately), and so there is a colour difference that I haven't gotten rid of.