of the Mercado Area
When molded clay is heated to a high temperature, its clay particles fuse with one another. When the molded object cools, it hardens and keeps its shape and, depending on the temperature it has been fired at and the nature of the clay it is composed of, it will be partially or entirely impervious to the passage of liquids.
The simplest kind of pottery, one baked at relatively low temperatures, can be called unglazed earthenware. This is nothing more than moist clay baked until it is hard. It is "unglazed" because its clay particles have not melted to form a vitreous, or glassy-smooth, surface. Unglazed pottery is rough to the touch. The animal figurines and pottery produced by María Lopez Lopez in Amatenango del Valle, Chiapas, introduced in our "suppliers" section, were unglazed earthenware. María simply placed her clay creations inside a stack of firewood, set fire to the heap, and hoped for the best. With such uncontrolled firing, probably it was inevitable that many of her pieces cracked as they were baking. Bricks and terra cotta are forms of unglazed earthenware.
If earthenware is baked with such high temperatures that the clay on its exterior acquires a slight glaze, it can be called lustrous ware. If ordinary clay is coated with a truly glassy coating, then it is glazed ware. Some would say that real glazed ware must contain lead. However, now that everyone worries about this dangerous heavy metal soaking into food cooked in lead-containing pottery, most vendors swear that their glazed pottery contains no lead. Lead poisoning is such a serious matter that I'm not sure what to advise if an extremely lustrous pot catches your fancy.
Stoneware is pottery made of high-silica clay, which when fired becomes particularly hard and impervious to liquids. The term graniteware can be used for pottery made of high-silica clay that is light colored and coated with a glassy, or vitreous, glaze traditionally containing lead. Porcelain is the most delicate type of pottery. It is made of kaolin, a very fine-grained, white clay, and is not produced by traditional Mexican artisans.
Among Mexican towns producing the finest pottery are Tonalá and Tlaquepaque near Guadalajara. In Michoacán, near Pátzcuaro Lake, the ancient capital of the Tarascan Indians, Tzintzuntzan, still produces superb traditional pottery. In Oaxaca, in the town of San Bartolo Coyotepec, about six miles south of Oaxaca City on Mexico 175, a famous black pottery is available in both glazed and unglazed forms. A similarly fine, green, glazed pottery comes from Santa María Atzompa, on a small road just west of Oaxaca City. Potters in both towns use the same clay; the black pottery is black through and through, but the green is black inside, with a green glazing. Puebla produces some of the most ornate, commercially successful pottery, some of which is shown in the picture at the left. Remember to take a look at the introduction to talavera introduced to us by the Paria's Javier Pérez Domínguez, in the "Suppliers" section.
Mexico's ceramic output is hardly limited to pottery. Among the most popular baked-clay items purchased by tourists in central Mexico are árboles de la vida, or "trees of life," produced mainly in Metepec, a southeastern suburb of Toluca. These trees, which can stand several feet tall, are fantastically elaborate, and bear among their branches multitudinous figurines of animals, flowers, fruits, angels, and just about anything.
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