Antique English Staffordshire transfer china butter dish or cheese keeper (I think? Though I suppose it could be a soap dish?) It's about 4" square over the interior of the dish, and has a removable china insert as shown.
It's heavy ironstone or semi-porcelain china, marked PB& S (Powell, Bishop and Stonier) Chelsea pattern floral in brown, circa 1880s. It's very shabby and rough, with spots and stained chips and hairlines.