Metal detecting find

I found this item while metal detecting on my father-in-law's land yesterday. It is not magnetic and has a greenish tinge on it. The lettering looks old in style the letters that I can make out are may be a K followed by ETTE the last letter is missing. On the left is the letter I and on the far right are the letters O AND R. I found it on some land at Watery Lane which is near Sheepy Magna and not far from one of the Battle of Bosworth lines. Any information on this subject would be a great help.

Ah! metal detecting, I done it for years and still got loads of finds. The lettering appears to have been stamped on, could it spell KETTERING? Sorry, this is all I have to offer.