If light areas appear on polished black ware, it is safe to assume that they were brought about by lack of proper ventilation within the oven during the preliminary burning, such as would occur if two vessels were so close together as to prohibit the free passage of air. If white slip is touched just before burning, the oil from the fingers is apt to be fired in, thus ruining the uniform appearance of the surface by the potter’s indelible fingerprint. To avoid such an accident, polychrome vessels are usually handled only by the interior of the rim on the day they are burned.
Underfiring and overfiring, with consequent damage to the ware, are usually due to gross carelessness on the part of the potter in the irregular placing of kindling. The wind also has something to do with it. If there is a stiff breeze blowing, the probabilities are that the windward surfaces of vessels within the oven will be underfired, while those in the lee of the vessels will be overfired.
PLATE 28
Courtesy Amer. Mus. Nat. Hist.
ZUÑI. PREPARING CLAY
a. Pulverizing dry ingredients on flat stone slab with a mano or hand stone.
b. Wetting, mixing, and kneading clay; water-container in foreground; prepared clay in bowl.
PLATE 29