Does this pottery box with impressed marks look recognizable?

I'm thinking it's Japanese art pottery, but not sure. Doesn't look very old at all, but the owner said it came from her "Mimi"'s house in Mississippi. I'm assuming that's her grandmother. Anyway, it's about 6" across, and the marks to me look like an "R" inside the left hand box and an "AB" inside the right hand box. Thanks for any input.