THE POTTERY OF SAN MARCOS TLAPAZOLA, OAXACA. PART I

MAKING CLAY AND FORMING VESSELS IN SAN MARCOS

an Marcos Tlapazola is a Zapotec village in the valley of Oaxaca where the principle trade of the women is pottery making. For at least 1,500 years and perhaps as many as 4,000 years, the potters in this village have been making utilitarian pottery using techniques that have changed very little over the millennia. Part 1 of this article illustrates how the clay is made and how the vessels are formed. In part II we’ll look at the firing process.

MAKING CLAY

Step 1) Getting the Clay. The clay used in San Marcos Tlapazola is found just beneath the topsoil in thick deposits. The catch is that most of the deposits are under corn fields. So the potters can only mine their clay between January and May, which is the window of time after the corn has been harvested and before cultivation begins again. In this time the potters stockpile as much dry clay as they think they’ll need for the coming year.  The clay is brought home and left to dry. Clay is curious. It will dissolve perfectly if it is perfectly dry. But if it has even a little moisture in it, it won’t dissolve at all! So the potter begins her preparations with perfectly dry clods of clay.
Step 2) Soaking or Slaking the Clay.  The potter prepares her clay on a weekly basis, making as much as she’ll need for that week. She will take a bucket full of clay clods and dump them into a large pot. This is then filled with water and the clay left to dissolve. This happens rapidly and she can come back to that pot 15 minutes later and find mud instead of clay. With her hand and arm she will stir this mud and water stew until all the clods are broken down and the goo is a fairly even consistency.
Step 2) Clearing Out the Chaff. Knowing that the heaviest particles, sand and gravel, will settle to the bottom and the lightest will stay at the top, the potter enlists the aid of gravity in her process of purifying this earthy clay. She stirs up her pot of mucky clay, maintaining a soupy mixture. As she stirs, gravel and sand settle out while at the same time clay, which is very fine, dissolves turning the water creamy thick with its particles. Using a gourd, she scoops the thick water off the top, being careful not to dip too deep and catch thicker, less pure liquid from below. She pours the clay-loaded water through a sieve and into an adjacent pot. The sieve catches pieces of roots and other light material. This process is continued until the pot of muck has been completely processed and finally the sand and gravel from the bottom is rinsed as well to get every last bit of clay off of it and into the adjacent pot. What goes into the adjacent pot is the good stuff, pure clay and water. This is then left to settle over night.
Step 3) Settling the Clay, Removing Excess Water. Overnight the contents of the pot settle, heavier clay moving down, lighter water moving up. Because there is too much water in this clay, she carefully scoops off the clear layer of water at the top. What she is left with is a pot full of pure clay about the consistency of thin cream. 
Step 4) Sifting Sand. Sand needs to be added to the clay mixture as a strengthening and tempering agent. Using screen that comes from a certain kind of market bag  nailed to a wooden frame, the potter sifts sand that she’s collected from the creek banks, letting only the finer particles fall through. When she has enough sand to fill the bucket she used to measure her clay into the pot in Step 2, she pours this sand into the pot with the creamy clay. In other words, in the case of San Marcos, there is a one to one ratio of clay to sand or temper. This ratio is fairly common in Mesoamerican pottery.
Step 5) Mixing and Spreading. This is the fun part. Using her arm as her stirring spoon, she mixes the soft, warm sand with the cool, smooth clay until the mixture is completely even. Through experience and feel she knows if the mixture needs more sand and will add it as necessary. Different kinds of vessels require different mixtures of sand. For example, because of their more open, and therefore more fragile forms, Bowls and comales require more sand for strength than round pots. Once prepared, the mixture is about the consistency of molten fudge, much to wet to work with. The potter will sweep clean a piece of hard soil in her courtyard and with her sifter, lay down a thin layer of sand, much like putting flour on the cutting board before laying out the dough. Using a scoop she will slowly, gracefully pour her liquid clay onto the sand-dusted earth. When it is all poured out, she has a large, level pancake of clay in the middle of the courtyard. She does her best to keep chickens and children from rambling through the middle of it. The heat of the sun will slowly dehydrate this pancake, from the edges inward. As she sees the edges beginning to crack she rolls up the clay, bit by bit, and takes it inside to her cool work space. It is now the right consistency for working with and the last thing she has to do is knead or wedge it before going to work.

Working Clay Without a Wheel



The potters of San Marcos work with an ingeniously simple kind of Lazy Susan. The potters use a slab of stone or heavy brick as a base. To prepare the stone for use initially they grind a small dent into it. When the potter works she puts a bit of sand into the dent, which acts like ball bearings, and then sets a scrap of an old soccer ball into the dent. Voila!, she has a Lazy Susan. Into the scrap of the soccer ball goes the pointed end of her cone, the pivot point for the rotation of her pot has she works. She is not throwing her pot as we are accustomed to doing on a wheel, but simply rotating it constantly as she hand builds it to ensure roundness and an even consistency

 FORMING

The forming method used in San Marcos is unique to this village, as is the dialect of Zapotec spoken here. But just as other villages speak similar, but slightly distinct dialects of Zapotec, other pottery villages use distinct, but similar methods to form and fire their vessels.

The potters in San Marcos will usually work on a set of 20 or so vessels each week and fire them on the weekend. Typically the fired pots will be taken and sold at nearby markets.

 

Step 1) Forming and opening the cone. The fresh clay is wedged and then formed into a cone which looks something like a large and muddy Hershey’s Kiss. The  size will vary depending on the size of the vessel. The potter will then push/punch a deep hollow into the wide end of the cone with her fist. Now, using a corn cob like a rolling pin she will begin to thin the walls of the cone and effectively “pull” her vessel up. She does this by rolling the cob on the outside of the vessel with her left hand and supporting it from the inside with her right hand, very much like rolling batter on a cutting board. As she works she rotates the pot, evenly thinning the walls as she goes.
Step 2) Building up the vessel.  Having begun the form on its side, she now sets it upright and continues the process. She places the point of her cone on her Lazy Susan . She will continue the same process with the corn cob rolling pin, now working vertically. At this point, to pull the sides of her vessel higher, she will need to add additional clay. She does this by adding a coil of clay onto the inside of her vessel just below the rim. The now thicker rim can be rolled or pulled with the rolling pin, effectively making the walls higher while at the same time creating a perfect bond between the new coil and the existing clay. This process will be repeated until her vessel has reached the size she wishes it to be. Of course as she works she is constantly rotating the vessel.

A Potter's Tools: Simple and efficient

The tools used by the potters of San Marcos, like the tools used by potters all over Latin America, or simple and effective, and almost always recycled or recovered from some other use. The lazy susan is often made from an old metate (corn grinder) and the disk for it comes from old soccer  or basket balls. The key forming tools are corn cobs, coming from, of course, harvested corn. The gourds typically come from broken gourd bowls. The old piece of leather might come from on old shoe. And these are the only tools used for forming. Trimming requires another tool, the strapping metal. This is salvaged from the reinforcing rings found on the bases of worn out sheet metal buckets. Of course the most important tool of all are the hands, and the generation experience found in the master potters who put these hands to work.

 Step 3) Giving the vessel form. The uses a gourd like tool called a jicara (which comes from the gourd trees along the coast) as a rib to shape her vessel. Choosing the correct-sized jicara, she will begin to push out the belly of the vessel, while at the same time compressing the shoulder and rim inwards, much like a potter throwing on a wheel would do. However, she will use almost no water for any of this process. Using a thick, stiff piece of leather, she shapes the rim, and finally, using a smooth, concave corn cob, she smooths off the outer surface of the vessel. It is then set aside in a cool spot to firm up.

Step 4) Refining the form. This is usually done on day two. The belly of the vessel will be pushed out more, perfecting the form. A small coil of clay will be added to the rim and refined to give the rim a final finish.

Step 5) Trimming.  This is usually done on day 3. When the vessel is leather hard it is trimmed using a piece of recycled strapping metal. The point of the cone, which has remained intact until now, is trimmed off and the bottom of the vessel is rounded. As the potter trims she always has one hand on the inside, pushing against the trimming tool and sensing the thickness of the pot. When she is done she will have trimmed the pot walls to an almost perfectly even thickness of ¼ inch or less.

(Step 6) Slipping and burnishing. Typically done the afternoon of the final trimming. The pot is slipped with a yogurt thick iron oxide slip. The slip comes from deposits about 2 hours up the mountain from the village. The slip is spread evenly over the pot and then left over night to firm up.   The next day, with considerable elbow grease, the vessel is burnished with a piece of quartz. And it is now ready for the fire.
San Marcos Pottery-Making Part II Coming Soon!

Traditions Mexico Oaxacan Clay Workshop
January 3 -11, 2009
For more images of the San Marcos pottery-making process, see our slide show

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