Butterprint (1957-1968) Cinderella round casseroles. The all turquoise on opal 470 set at left was a limited offering, as was an all pink on opal 470 set. Normally, the 471, 473, and 475 are white on turquoise like the dish at right. Limited run, promotional, and stamp program set patterns were often printed on plain, unpainted opal, ostensibly a production cost saving measure. Ironically, those like the pink Butterprint 470 set and the orange Butterprint 440 set are among the most coveted by collectors, and typically the most expensive to acquire.