MAKING PROCESS
- Clay selection. The glaze and clay of Jian Zhan need to have high iron content. Other kilns in Song Dynasty have tried to imitate Jian Zhan, but they usually cannot succeed for the minerals in their geographic location can hardly meet the standards of making a Jian Zhan.
- Crushing. To place the prepared clay and glaze in a machine for pulverization
- Washing and sieve. The thickness of the clay or glaze should be moderate. After sieved, the clay need to be put into the slurry tank, while the glaze need to placed in the glaze pool.
- Chen Fu, which is a ceramic terminology, refers to place the clay in a room away from sunlight and air, keep a certain temperature and humidity, and store it for a while.
- Knead the clay. This process is aimed to further remove the air and impurities in the clay, make the mud dense, uniform humidity, and facilitate forming, meanwhile, it also prevents the clay from drying and cracking during post-production.
- Shaping, usually divided into hand shaping and machine shaping.
- Modification. The traditional shape of Jian Zhan is mainly shallow circle foot, and the base part and the “inner ring ” of the foot need to be modified by knife.
- Kiln the unglazed Jian Zhan. This process can increase the mechanical strength of the clay, and also remove a part of the cracked and fragile Jian Zhan in advance.
- Blend glaze. The glaze formula of the ancient method is to use natural iron ore glaze and plant ash. These two simple substances can compose the beautiful glaze, which looks incredible, but the craft of making Jian Zhan is to use the simplest materials to creat the most mysterious crystals.
- Glazed. One of the big featured of Jian Zhan crafting is the half-glazed. Ancient people would specially design a glaze line to facilitate the control of the glaze range. Glazing also needs very skillful technique, ensure the glaze moderate. If thin, the room for the growth of crystal is too small to produce a delicate works; if too thick, the glaze may easy to stick to the bottom.
- Put into the kiln. There usually need to place a layer of alumina powder on the bottom to avoid stick.
- Kiln and fire the Jian Zhan. The kiln is the most important process of making Jian Zhan. If the time, degree and frequency of reduction are not well mastered, the desired glaze color will not be successfully created. After put into the kiln, the master must be concentrate on controlling the degree of reduction and not leave for a long time.
- Finishing kiln. After kiln, due to various restrictions on the making process, each kiln will inevitably produce defective products, which must be disposed of on site. Products that pass the quality inspection can be sold.
Tenmokus foster color
Because the material on the surface of Jianjian is mainly two substances, iron (iron tire as well as high iron amount of original mineral glaze) and alkali (tea broth), the tea broth and iron have a chemical reaction, thus allowing the structure of the material on the surface of the jianjian to change and the color to change as a result. The substance on the surface of Jianjian is infiltrated by the tea broth, absorbs the tea scale, and under the light, a refractive surface is formed on the surface, thus producing a different luster than before. I think that the "color" is the reaction of the daily use of Jianjian, the reaction of the tea soup and glaze pulp to form a film, the formation of seven colors on the surface of Jianjian glaze.
We usually raise the calendula use process, ①every day after the last tea, rinse with boiling water to remove the tea scale attached to the glaze, and then the natural placement of Jianjian, ventilation can be. It is best to use a special tea cloth to wipe it clean, and every four or five days, a more detailed wipe will be good. ② Never put the tea in the calendula to stay overnight, soak do not exceed 30 minutes, or deliberately do not clean the calendula, which is a great harm to the calendula.