While at an antique store in rural Kentucky last week, I purchased what I feel is a unique square pottery bowl that is very similar in shape and size to one listed on eBay as "Bauer Pottery Matt Carlton Square Jade Art Bowl! VERY RARE!". However, I have received one opinion from an on-line antique dealer that it is not Bauer.
The store owner informed me that the bowl belonged to her son who is an antique dealer and that is was a "real" antique. The sticker price was $28 but her son would go no lower than $15.
The bowl measures 5" across at mid-body, 6" measured diagonally across the square and stands approximately 1.5 to 1.75". The glaze is matte yellow (similar in hue to Dijon mustard) with pale red-violet swirl/speckle asymmetrical design on the outer edges. The design is difficult for me to describe since it is muted in some areas and concentrated in others and I have been unable to find anything similar searching online.
There are no marks on the bottom center, but there is either an imperfection in the glaze or a mark on the bottom rim. The mark is indiscernible to me, but my husband says it looks like there could be letters MA and 2 other letters or numbers within the area of the mark that could have been circular and marred over time (his eyesight is far superior to mine).
Note that many of the pottery items for resale in this area of Kentucky were made in ohio. Such as McCoy, Roseville, Brush, etc.