Onggi is collectively referred to as the bowls of both glazed oji and unglazed jil earthenware bowls. The following summarizes the concepts of clay (jil) unglazed earthenware, oji earthenware and onggi.
The unglazed earthenware has been used since Neolithic age, and it is made of clay only at the temperature of 600~800℃. By blocking the chimney and the muffler, it is divided into black bowls covered with soot and natural air, so that the air is oxidized and red bowls are oxidized. It has a relatively strong water absorption and can control moisture, so it has a clean effect. In addition, since it is a form of soft pottery, it has a property that is easily broken, so that the progress of going back to natural earth is easy. It is widely used for kitchen, farming and living.
Oji earthenwares are pronounced as ‘Oji’ or ‘Uhji’, and are also called lacquer bowls or painted bowls. Clay is used as a ceramic and coat with lye (lye glaze). It shows the shape of hard ceramics by oxidation at the temperature of 1,100~1,200℃. It is somewhat rough and less glossy and not delicate in terms of cross-linking, but because of its similar relationship with Onggi, it had been called as earthenware and now became a part of Onggi.
Onggi was originally used to refer to the term “jar,” but as time went by, the whole earthenware came to be enclosed. After clay is formed into ceramic, it is a container that is fired once at a temperature of 1,100~1,200℃ after coating with medicinal soil, a kind of vegetable soil and ashes. It was used in most of the daily life containers, including storage and fermentation.
- Characteristics of Onggi
Glaze makes the ceramic harder, prevents water leaks, and has a glossy and decorative effect. Glazing is a difficult task that adds time and production costs. Therefore, in comparison with the earthenware and Pure bowls, which are free of glazing, Onggi is a very high-grade earthenware.
Glazing method began with lead-glazed earthenware that initially melted at low temperatures. In the Three Kingdoms era, earthenware production was carried at low temperature, but under the influence of China’s Tang Dynasty, earthenware production began in earnest at high temperatures. The glaze is the lye-glaze mixed with lye in red clay with high iron content, that is, the ash glaze type. Colors are yellowish brown, greenish brown, and black. The color varies depending on the iron content of the soil and the temperature inside the kiln.
Later, the lye coated in small bowls was a glaze made of half red clay and half ash. It was settled as Onggi glaze after Goryeo’s black glaze and Joseon’s glaze. Glazes should be applied on slightly dried bowls in half shades. It's often called “lye clay.” First, the clay and pine wood from the rice paddy are mixed with a volume ratio of 6:4 or 5:4 to make the muddy water, and the muddy water is filtered once again to remove the miscellaneous material and then sinks until the water becomes clear. Discard the upper water and use the lower water for glazing. Dip the glaze you made into the glaze container, gently soak the molded bowl, scoop it up and turn it over to let it turn red. The glaze spilled during the milking process produces a natural or abstract beauty after firing.
Onggi’s glyphs can be divided into glyphs formed during the molding process and glyphs generated during the process.
The decorative glyphs in the molding process are naturally created and intentionally created during the process of making the earthenware. In the process of smoothing the surface by hitting with a bat with a woodcut or a rope or symbols engraved on the water wheel placed on the bottom of the earthenware wheel are naturally formed patterns. The representative artificial glyphs that were intentionally created using hands and tools include geungaeddi, mokjulddi, sonddi, apinmun. The geungaeddi (the ladder-shaped tool made of persimmon tree or duckwood) is inserted into the root line. Inside and outside the walls, there are hand straps that hold both hands and rotate the spinning wheel to create a glyph, and pressure humanoids that press and decorate the walls at regular intervals using tools.
After applying the glaze on the first dried earthenware, the patterns are applied on the surface of the earthenware using hands or roots. The sign language in this process expresses the liberty, speed, and simplicity of the common people.
In Chuihuamen, there are Hohyeong-mun, Yongsucheol-mun, Pagokseon-mun, Pasang-mun, Sanhyeong-mun, Wun-mun, Hae-mun, Cho-mun, and Jukyup-mun.
③ Regional characteristics of Onggi
Onggi looks different depending on the natural environment of each region. Depending on the region, types, techniques, and patterns are not uniform, but each has its own unique form.
The Gaeseong region has rounded shape, and was engraved on the surface with engraved lines or embossed lines, or fish and glyphs.
Pyongyang’s bowls are similar to Gaeseong’s in their overall appearance. They made their mouths wide so that they could receive a lot of sunlight in the container so they could withstand the cold.
Seoul and Gyeonggi-do have a slim and slender appearance, with similar size of mouth and bottom diameter. It has various patterns painted with roots and by hand. The central region is the central region of the northern and southern provinces and is a compromise between the other two provinces. The lid is characterized by the use of a lotus bud-shaped handle.
Gangwon-do has a look that is similar to that of Gyeonggi-do. The inclination of the shoulder is steep and the mouth is wider. In addition, small forms of Onggi can be seen, which are easy to transport in mountainous areas.
Chungcheong-do has a high neck and a little bit outward shape, and the glyphs show the appearance of crucian carp, orchid and butterfly.
Jeolla-do has a wider mouth and wider belly than the mouth. It circulates from the shoulders to the bottom. Patterns include forests, carp, grapes, and caps with helmets or three-story round towers. Occasionally, a soraegi is covered as a lid.
Gyeongsang-do has prominently protruded from the trunk, narrows sharply from the shoulder to the mouth, and the mouth is very small, and the shape of the shoulder is angled.
Jeju Island has a narrow mouth and bottom, and is called abdomen. It is made of volcanic soil and contains a lot of iron, which is red in color. In addition, due to its insufficient production capacity, a considerable amount of pottery was imported from the land, and the culture of pottery was not developed so well.
However, the regional characteristics of Onggi were gradually lost due to the expansion of the road network due to economic development and the development of transportation methods.