This is a fascinating pottery bowl - we are not quite sure whether it is a summer chawan (teabowl with slanted sides for use in the summer) or a sake bowl. The bowl was acquired years ago from an estate and the person who consigned was told by her grandmother that it is from the early 1800s and had been in the family for generations. The bowl measures 6" diameter that the top by 2 1/8" high at the rim. The low footed base is 2" diameter. We date the bowl to the late Edo period, circa 1800-1830s.
Interestingly the interior has only a thin greyish tan - whilst the outer sides have are glazed with this fine underglaze cobalt blue design under a very thick pebbly surface glaze that it reminded of Shino Pottery glazes. The design might well have been for the Persian market as it looks like many of the Iznik designs we have seen on Persian ceramics. Regardless of its origin, it is a lovely bowl with only a couple of short stable hairlines and a circular kiln flaw - all of which clearly occurred during the firing process.