This is a Rowe Pottery Works 2 piece butter dish in the rectangular shape.  It has the Rowe emblem impressed on the bottom but no date.  It is in very nice condition, but was probably a second because there is a very light black x on the very bottom.  No chips, cracks or crazing, but there is one very small dot on the bottom edge of the lid that missed the glaze.  Note the blue swirl design on the tan body. 

Shipping weight will be 3#.