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The Onggi Potters of Korea
by Ron du Bois

(color only)

This article consists of three parts:

  1. Article: The Onggi Potters of Korea (this page)
  2. The work of Korean folk potter Heo Jin Kyu
  3. The work of Korean folk potter Yon Shik Bae


Korean pottery today is still largely produced as it was in the past. For a practicing potter it provides a living case study of historical ceramic processes and techniques. Potter's wheels, kilns, tools and other equipment are still made as they were in years past. Machinery is too expensive to warrant its purchase and maintenance relative to the cost of man power. Glaze materials are still ground from the parent rock materials using ingenious two-man pounders. Within a period of six days, two men working full time can only produce about sixty pounds of pulverized material. No ceramic supply houses offer ready made equipment or processed materials suitable for instant use. Immense quantities of wood must be transported, chopped and split. In the Vi dynasty the proximity of kilns to forests was more important than to kaolin deposits. Today the forests-are seriously depleted; special permits are issued for the purchase and burning of wood. It is an expensive fuel but less so than either oil or propane which are imported products. Natural gas does not exist.

The complexity of the ceramic process is taken for granted, as is the necessity for a division of labor. Chopping wood, mixing and decanting clay, slicing, stacking and firing are assigned to specialists. The authorship of the pottery when it emerges from the kiln is diffuse, since it is the result of the coordinated effort of many hands.

There are four major categories of ceramics produced in Korea today:

  1. Onggi, or earthenware utensils, used for a variety of purposes, but primarily for the storage of pickled vegetables, bean pastes and soy sauces - staple items of the Korean diet.
  2. Reproduced Koryo and Vi dynasty forms, for sale primarily to the Japanese market.
  3. Tea bowls, again for the Japanese market.
  4. Pottery produced within university ceramic departments, reflecting, in varying degrees, exposure to outside influence.

Of the above categories, onggi is of the greatest interest to the Occidental potter. The techniques and methods used are virtually unknown in the West. The Korean potter is able to produce monumental size jars with a speed that seems incredible when witnessed by a Western potter. The methods of coil, paddle and wheel construction are outside the spectrum of ceramic skills in the West, particularly in terms of speed and size.

Because of recent developments in the use of various metals, artificial resins, and the growth of in9ustrial ceramics in Korea there is a danger that the production and use of hand· crafted vessels will die out. Moreover, modern materials and processes may be found to be preferable to onggi ware, which is less durable, heavier and higher in price than mass produced pots. Working against this possibility, however, is the conservative character of Koreans and their firm belief that the taste of kimchi would be adversely affected by storage in anything but onggi ware. On the other hand, the new reforestation laws pose a fundamental danger to the continued firing of onggi kilns. Wood is scarce and expensive and imported oil is more so. There seems to be no solution to the high ecological and financial costs of fuel. Thus, it is difficult to predict the future of onggi pottery in Korea. But, for the present, at least, the Western potter is still able to observe the traditional skills of the Korean potter.


Clay Preparation

Beginning in the 1950's, the onggi potters started to adopt a traditional Korean technique of refining clay that had hitherto only been used in the manufacture of high-quality white ware. Thus, the methods described below are essentially the same both for onggi and porcelain ware manufacture. About twenty years ago, some onggi workshops on Kanghwa Island adopted that technique, and its use spread gradually to Kyonggi and South Ch'ungch'ong provinces.

A field approximately 75' x 75' is used for the drying of clay. At each corner of the field a round hole approximately eight feet in diameter is dug out. These are settling vats. Today they are sometimes lined with cement. A smaller rectangular vat approximately two by four feet is built tangential to each of the circular vats. Small wooden connecting dykes allow water from each settling vat to flow back into the mixing vat as water is needed. Raised earth levies divide the ground between the mixing and settling vats into drying fields. In addition they serve as dry footpaths from which workers are able to remove the dried chunks of clay.


Refining Procedures

  1. Drying. The raw clay is dried in order to assure that it will slake more quickly in the refining vat. The clay is scooped up with a "three-men shovel" and piled in a sunny place to dry. It is then spread and evened with a wooden rake or hoe. Lumps of clay are broken with the hoe and large stones are picked out. The clay, in the form of soft shale, does not break or slake easily. The dried clay, broken roughly into lumps no larger than apples, is taken to the refining area in a basket or cart. Often an A-frame is used to carry about two hundred pounds to the mixing vats.
  2. Mixing and slaking. The clay is dumped from the cart or A-frame into the mixing vat containing water. After the clay has begun to dissolve in the water, it is stirred with a wooden paddle to which is affixed a handle with a cross bar at the end. The clay is levered up and down using the edge of the mixing vat as a fulcrum. The soft shale does not slake easily and a constant up-and-down motion of the paddle is necessary to partially dissolve the clay and produce a watery slip. The mixing process involves long and repetitive labor; women are assigned to this task since they can be paid less. To the Western observer it seems incredible that so much labor is expended on a process that could be accomplished easily and quickly by an electric blunger.
  3. Screening the clay. The thin slurry thus produced is scooped out with a bucket and poured through a thirty-mesh screen into the second or settling vat. The screening assures that clumps of clay, sand and pebbles do not enter the second vat. When more water is needed to continue the mixing process, that gate of the small dyke is removed. The relatively pure top layer of water from the second vat flows back into the mixing vat.
    By repeated mixing, screening and return water flow the clay in the vat is eventually used up, leaving only stones and sand. These are removed with a shovel; more water and raw clay are added, and the process is begun again. Approximately a week is required to fill the settling tank with thick slurry. When the second vat has been filled with screened clay slip, it is scooped out with buckets and taken to the drying field, using the raised levies as walkways.
  4. Drying the slip to the plastic stage. The ground of the storage area is first covered with a layer of hemp or cotton cloth about 15' x 15' in order to prevent impurities from the ground getting into the clay and to facilitate removing it when it dries to a plastic stage. The clay slurry is spread on top of the cloth and the moisture in the clay is evaporated by the sun and wind. When the clay has been dried to a plastic stage, it is scored with a small scythe and the chunks approximately 12" x 12" x 6" are carried to a cart, in which they are transported to the workshop.
  5. Further preparation of the clay. In the workshop the chunks of clay are stacked to form a rectangular mass approximately six feet in length, four feet in width and four feet high. Water is sprinkled on the clay and it is beaten with a long wooden mallet, first with he head, then with the side, by workers mown as saengjilggun. The clay that has been tacked on the workshop floor is then cut into thin slices about 1/8" in thickness with a scythe-like knife. This part of the second processing is performed by workers known as 'hardy lads" or "clay slaves." The main reason for slicing the clay is to homogenize the distribution of soft and dry clay.

    The "hardy lads" next roll the clay into balls weighing forty or fifty pounds. In some workshops, a sheet of cotton cloth is laid on part of the workshop floor and the balls of clay are put on top of this; in others kaolin is spread directly on the earthen floor.

    The balls of Clay are stacked up until a rectangular mass 10' x 10' x 3', i.e., about two and one half tons, is formed. The clay is always beaten first with the head of the mallet, then with the side of the mallet. The mass of beaten clay is then sliced a second time into balls and, for the second time, pounded. After the second pounding the mass of clay is then cut into chunks using a wooden shovel which is carved monoxylously, i.e., from a single piece of wood. These chunks are turned over to form a new mass which is again pounded and cut with the wooden shovel into about hundred-pound squares of plastic clay.

    Clay prepared in this way is as well mixed as by a pugmill. In addition, the pounding of the clay may account for the peculiar wet strength and toughness of onggi clay. Several squares, which will be put to use immediately, are set aside and the rest are covered with a damp cloth or plastic sheeting to keep them from drying. The thick sod walls, heavy thatch roof and small windows of the workshops are deal for retaining the moisture content of these "mountains" of clay.

    The squares of clay that have not been covered are taken to a place just beside the potters' wheels where they are cut by wire into oblong shapes about 18" x 3" x 3" weighing some twenty pounds.

Coil Construction

A "hardy lad" quickly moves one of these oblongs to a relatively flat area of the earthen floor where he begins to make lateral throws of the clay, quickly extending its length to some 36 inches. This bar is slightly twisted to form a spiral cylinder of clay. The techniques of twisting the clay bar assures the easy transition from bar form to a smooth even coil. The coil is next reduced to a diameter of 1 V2" and extended about 6 feet in length by rolling it backwards and forwards on the earth floor. A pile of these coils is laid next to the potter's wheel ready for use.

Forming the Base of the Vessel

A ball of clay about eight pounds in weight is hand wedged into a cylinder about 41/2" in diameter and 6" long. This roll of clay is picked up and given several throws on the earth floor so that a thick disc is formed. This is expanded to about 16" in diameter and 3" in thickness by a series of rotations and lateral throws. The disc is placed next to the potter's wheel. The process is repeated until a stack of discs are made.


Flattening the Disc

The potter now positions himself at the wheel and rapidly dusts the wooden throwing head with dry kaolin powder. The powder prevents the disc from adhering too strongly to the wheel head and allows the finished pot to be lifted from the wheel. No cutting wire is used.

Next the potter centers the disc on the wheel head. While slowly turning the wheel in a counterclockwise direction, he quickly beats the clay disc with the pangmangi, or beating stick, which he holds in his right hand. This thoroughly compresses the particles of clay and removes air pockets. The potters place great emphasis on learning this; if it is not done correctly, the bottom will crack either in the drying or firing stage.

Wall Formation - First Stage

The potter inscribes a circle in the disc to mark off the base size desired; then he revolves the wheel and cuts off the excess clay with a wooden knife. Next comes the task of fashioning the walls of the vessel. At the present time there are three methods of constructing the walls, each differing slightly from the others. The most common are the "coil" method, used in Kyonggi province, and the "spiral coil" method used in Kyongsang province. The third, even more startling to the Westerner, is the "slab" method, used in Cholla province. In this technique, long "slabs" of clay, about three times the diameter of the pot, 8 inches wide and 3/8 inch thick, are set one on top of the other to form the vessel wall. These slabs are constructed in approximately the same fashion as the clay coils except that the bars of clay, rather than being twisted and rolled into coils, are flipped in the air and slapped on the ground to form wide "ribbons" of clay.

The first stage of wall construction consists of connecting the base of the vessel with the bottom-most part of the vessel wall. This portion of the vessel wall may be fashioned of the excess clay from the disc of the clay used in making the base or it may be constructed of a cylinder of clay made especially for this purpose. A coil of clay approximately three times the diameter of the base is put on the wheel. The wheel is rev91ved slowly and the coil beaten flat. In either case, the flat strip of clay is then attached to the edge of the base. After this has been accomplished a thin coil of clay is taken and pressed along the inner seam between the base and the lower part of the wall. This procedure is done in, order to strengthen the joint between these two pieces of clay. It is executed with amazing skill, the knuckle of the right hand pressing the coil into the joint, the left hand providing exterior support. At the same time the wheel is rotated slowly with a rapid heel action of the left foot a method requiring motor skills entirely unknown in the West.

In the next step the potter takes a coil of clay and attaches it to the lower part of the wall already constructed. The technique used in coil joining involves a coordinated pressure of the left palm on the outside surface of the coil together with a series of half rotations on the right hand exerting a downward and opposing lateral pressure. This is performed with virtuoso speed and skill. The left foot, the toes and ball placed against the pit wall, function as a fulcrum for the heel of the foot to again perform a rapid series of forward motions, moving the wheel forward at a speed coordinated with the work of the hands. The process is repeated until three or four coils have been applied. In Kyongsang Province, where the "spiral coil" method is used, the coil, more than six times the diameter of the pot, drapes over the shoulder of the potter and down his back. He feeds it continuously for two or more revolutions of the wheel before the coil is used up.

Beating Techniques

The next step involves the use of a wooden anvil, or togae, and a wooden paddle. The potter beats against the inner and outer surfaces of the vessel wall with these two implements while at the same time revolving the wheel with his left foot in a counterclockwise direction. In this way the coils of clay are completely homogenized and the walls are thinned. In addition, the clay is compressed and thus becomes stronger. This completed, the potter takes up two scrapers. The one used as an inside scraper is usually a sea shell, although stiff metal scrapers are also used; the other is an outside wooden scraper which is larger. The latter is held in the right hand and the former in the left and applied to the inner surface. The potter, holding the scrapers rigidly opposed to each other, turns the wheel rapidly, "pulling" at the wheel with his left leg. To maintain this sort of strength in the muscles of the left leg requires constant exercise of these muscles. Sore leg muscles are inevitable if the potter begins to work again after a period of inactivity.

The next stage is the construction of the mid-section of the wall using the same sequence of coil application, paddling, and scraping. The same sequence is repeated to complete the top section of the vessel. This completed, the potter takes the wooden knife to trim the top edge. He then takes a moistened strip of cloth, the central section of which is laid on the top edge, the rest of the strip falling downwards on the inner and outer surfaces. Holding the strip firmly in both hands he turns the wheel, allowing the cloth to create a thickened lip form.

Final Procedures

With a shorter and thinner piece of cloth pinched between the fingers of the right hand he creates a raised linear decoration just above and below the "body" of the vessel. He supports the inner wall with his left hand as the wheel turns. The vessel is now completed, save for its removal from the wheel. He then trims the bottom of the vessel with "bottom cutter" or wooden knife, turning the wheel at the same time. For a large pot the potter gets the help of one of the "hardy lads" to lift the vessel from the wheel with a piece of cloth. The cloth, measuring about two by four feet, is wrapped around the vessel. The two men, positioned on opposite sides of the vessel, simultaneously pull upwards on the cloth, hereby lifting the vessel from the wheel. It is hen moved to a special shed called the iongch'im, constructed with thatch roof but without walls, where it is set down. The cloth is removed and the vessel is allowed to dry for several days, depending on temperature and humidity. It should be noted that the method of construction makes it unnecessary to trim the bottom of the vessel; even so, the walls of a pot four feet in height are uniformly thin from top to bottom.

Ron du Bois, potter and instructor of ceramics at Oklahoma State University, spent 18 months in Korea on a Fulbright scholarship. His work with the folk potters of Korea resulted in an award winning film, The Korean Potter, which can be obtained through The Daniel Clark Film Library, Box 315, Franklin Lakes, NJ 07417.

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