Okay, not the most thrilling discovery in the world but I'm weirdly invested.
Dog kicked this up on his walk this morning. We walk on a footpath that goes through the middle of a farmers field so it's ground that has been repeatedly ploughed. Am curious as I'm fairly familiar with the history of the area (family have lived here for several generations) and there are no houses in the immediate vicinity, unless you count the new build estate where we live and that's about a ten minute walk away. I know the land has been farmed with the same boundaries since the turn of the 18th / 19th century according to local tithe maps but the boundaries are probably much older - villages around it are Anglo Saxon in origin but a lot of Roman coins have been found in the local area as well as Mesolithic tools.
My very uneducated guess is that it's the base of a stonewear pot that some old farmer has used to keep his lunch in back in the day but to be honest I've no idea.
Any more educated guesses?
It looks like stoneware with a sandy / brownish glaze, and the curved bottom is about 6cm.