Small Unglazed Pot Japanese or so Styled - Chop Mark

I acquired this little pot some time ago and have been curious as to its origin. My instinct is that it is Japanese or certainly in that style. Lest the photos don't convey it is of black or dark brown unglazed pottery. It measures about 3" tall and 4.5 across at the widest point. It is marked with an impressed (chop) mark resembling a fan or leaf. Any ideas would be most welcome. Thanks