Acoma pots have long been noted for their thin, light, strong walls built up with layers of coils (photo). The white surface, characteristic since 1850, is achieved with a slip made from a pure white clay. Turn-of-the-century painted designs introduced red into previously all black motifs, and included a myriad of geometric designs based on historic and prehistoric forms: swirls, circles, zigzags, and hatching. Field photo: A. Dittert, Jr. and F. Plog, Generations in Clay, 1980