To burnish is to rub the surface of an unfired clay figure or pot with a hard object until it develops a semi-gloss shine. While the earliest known pottery can be traced to 12,000 B.C., the earliest known burnished pottery dates from 5,000 to 4,500 B.C. Used by the Badarian People of the Nile Valley to finish their red and black utilitarian ware, burnishing predates glazed pottery techniques and is consistent with low-temperature outdoor firing methods. Ancient people used burnishing to make their pottery harder and more waterproof before they discovered and adopted the use of glazes. The high temperatures required to melt glazes also required the development of kilns. Burnishing continues to be used by Native potters in the Americas, Asia, and Africa.
Burnishing is sometimes incorrectly called polishing. The two processes are related but different. Pottery novices might assume that all pots are glazed, and though glazed pottery can be brighter and more colorful, a burnished pot retains an intrinsic glow and warmth that glazed pottery doesn’t possess. The clay used in a burnished pot is not hidden behind a glossy and reflective millimeter of glass. The feel of a burnished pot is seductive. While a glazed pot feels hard and cold, a burnished pot seems warm and silky. Potters who burnish their work often see their customers handle their pots, turning them in their hands and stroking their surfaces. This is a common and unconscious response to the unique exterior that is rendered. While ancient potters developed burnishing to harden their wares, burnished pottery today is decorative and not meant to hold water or to be used for food or drink.
Burnishing is extremely time consuming and requires that the object be created of pure, fine clay. After molding or building the figure or pot, the clay is rubbed with a polished stone or smooth metal tool. In Tonalá, Jalisco, Mexico, pottery masters use pyrite or “fool’s gold.” The object is rubbed after it has been dried in the sun to a particular consistency. Minute areas are wetted and as the wet area is rubbed, a slurry is created that ultimately acts to close the pores of the clay’s surface. Slips or mineral paints can be applied or the surface can be rubbed with oil, animal fat, or wax and then burnished again before being fired to a cone 8 or to approximately 850 degrees F. Some burnished pottery is highly decorated, such as the work of Salvador Vazquez and Luis Cortez of Tonalá, Jalisco, Mexico, while others are left unadorned.
El Interior is fortunate enough to carry a few burnished pottery pieces, available in-store only.