What you have I believed at first was Majolica jug. I have seen the Circle K made in japan marks a few times, and thought it was a Import mark, for you find this mark on many items beside Pottery, Porcelain, toys and etc. But had to do a liitle snooping around a pit and found something intresting so I thought I would share, not sure what it all means yet, but just ran into it.
At this site http://chinaminer.canadutch.ca/index.php?pr=Japanese_info
Under this heading, Marumon ware, about halfway down
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An extensive search has not produced any details about the Marutomo at this stage. We know that the Japanese word “Maru” translates to mark or circle. We also know that similar wares appear with the names “Marumon Ware” and “Maruhun Ware”, only these brands appear with the circled letter “K”. A lot of Marutomoware is advertised as 1920-1930.
Marked on the base, Marumon Ware, the letter K in a circle, Made in Japan and Japanese writing underneath that. The Japanese were required to mark their exports Made in Japan , a practice which continued until the beginning of World War II, from 1941 until 1945. During the following years of American occupation of Japan (1945 to 1952), all exports from Japan were marked Made in Occupied Japan. After the Occupation, Japan marked her exports simply Japan.
It is believed that Marumon Ware was produced by a Division of the Noppon Toki Gomei Kaisha Company in the small town of Noritake. (See Noritake above)
