Nesting Stoneware Bowls set of four colorful Antique Mountainside Arts Pottery 1930s

Four gorgeous matching nesting stoneware bowls, in different colors, by Mountainside Arts Pottery. They operated in the 1920s and '30s, and the son of the owner made pottery using the same molds in the 70s, but these look like older ones, with stilt marks and no "made in USA" stamp. They almost but not exactly match; two pairs of very similar bowls, basically, with the same form but from different molds. The bottom two (when nested) are slightly larger than the top two, at about 10.5 inches and 10.25 inches. As happens with some Mountainside and unglazed-on-the-bottom pottery, some water crept into the clay on one bowl and has turned the glaze on the bowl's inside bottom a light purple, but it causes no harm and is pretty, actually (fourth photo, and it's basically the color of the bowl below it, though hard to tell from the pics). Hand-wash, and dry them and don't let them sit in water, and it won't happen (same as any piece not fully glazed). Selling as a set, but if you desperately want one color I'll consider it.