This is what I believe may be a Grueby Pottery Tile from the Arts and Crafts Era.   It is 7 3/4" in diameter.  It has crazing on the surface and I would guess this to be from the 1920s.   Has a G on the Back.   I am not an expert in this area.  Not sure on the maker, but is certainly OLD!!!!!!!!!    Quite Heavy for its size.   Insurance will be required.   As with all of my auctions,,,,,,,,,,********NO RESERVE********.  So, if you want it, BID!!!!!!!!!!!!!!!!!!!  High bidder pays shipping and thanx for looking.