How to distinguish between handmade and machine-made Zisha pots faster and more stable?

The difference between handmade Zisha pots and mechanism Zisha pots is as follows:

1, the smoothness of the inner wall is different

The handmade pots are shaped by patting the clay pieces directly through the patting, and the "injury" is basically on the outer wall, and the inner wall is basically unaffected by patting, and the texture of patting can be preserved completely before its molding. The tapping texture before molding can be completely preserved. And half-handed basically will not have, mostly scratched traces.

2, the bottom of the pot traces of different

Handmade zisha pots bottom and wall are separate, but the zisha clay is the same time modulation, this time difference caused by the pot after the fire, will be in the bottom of the pot to form a circle of obvious inlaid traces; if it is the mechanism of the zisha pot, after burning out, after the bottom of the cover articulation without obvious traces.

3, the number of seams is different

Handmade Zisha pots have only one joint, in the pot to install the handle can be seen in an inconspicuous seam line; mechanism of Zisha pots in the spout and the handle of the inner side of the pot each has a more obvious seam line.

4, the seal is different

The view of the inner seal according to the different types of pots, the view of the seal is also different. Whether it is round or square one thing is certain, the seal is the clay piece of flat laying on the time to cover up. See post also have another engraved on the inner wall, of course, this is also a way to prove the full hand, do full hand pots people can be described as good intentions ah. Usually, round pots of the inner wall of the chapter are generally varied

Expanded information:

Zisha pot firing process:

Zisha pots of the muffled ash firing process is through the use of other media artificially on the kiln phenomenon of a kind of application ~, in the firing process to make the purple sand pots change color uniformly a firing process.

During the firing of the dragon kiln, because the residue of thatched firewood not completely burned and the accumulation of charcoal ash, especially in the bottom position of the lower section of the formation of a local mixed reducing atmosphere, resulting in the phenomenon of discoloration of zisha pots. After feeling and summarizing the law, this kind of kiln change phenomenon is gradually granted to master the use. Early muffled ash is the purple sand pots into the sagger, inside and outside with huller and other stuffed with the whole sagger, cover closed after the sagger installed in the dragon kiln at the bottom position for firing.

Because the bottom of the dragon kiln does not have a mixed reduction atmosphere, sagger is generally used fine coal dust, wood chips and other carbonaceous fuels as filler, the formation of a localized reduction atmosphere. And the use of low-temperature (about 1100-1150 ℃) firing, in order to increase the product surface carbon adhesion capacity.

The adsorption of alabaster raw materials is very strong, and its own contains more organic matter and carbon, in the reducing atmosphere, these organic matter and carbon is not easy to burn out, and in the case of FeO at 400-600 ℃, carbon oxidation decomposition reaction is strongly carried out, the reaction of the carbon produced by the adsorption of carbon is adsorbed on the surface of the carcass, the oxidation of these carbons in a reducing atmosphere to be delayed to the end of the firing and the cooling of the The oxidation of these carbon elements in the reducing atmosphere to be delayed until the end of the firing and cooling of the initial period to burn out, so cover the temperature of the ash firing to be lower than the actual firing temperature.

And sealing the sagger filled with carbon filler, can reduce the free oxygen content of the combustion products in the sagger during firing, and isolation of the pot, so that the zisha pot in a good localized reducing atmosphere in the firing. Due to the carbon infiltration in the carbon filler, strengthen the coloring effect of zisha pots. Various kinds of Zisha raw materials due to their own chemical composition content differences, as well as firing temperature and atmosphere and other factors, cover the ash fired Zisha pots will show a variety of greenish-black color tone.

Muffled ash process

Muffled ash process is mainly a high iron content of zisha pots in the reducing atmosphere firing, so that the form of iron oxide in the raw materials to change the form of existence. Under normal firing conditions, the formation of iron oxide crystallization in the original alabaster most of the hematite fired in a reducing atmosphere, hematite is reduced to magnetite crystals, so cover the surface of the gray products have a certain degree of adsorption of magnetite.

Zisha clay such as green clay, such as a part of the lower iron content of the clay is generally not suitable to cover the ash fired (cover the ash fired more gray ink color, color effect is not good). Covered ash fired Zisha pots, such as in the neutral - oxidizing atmosphere of the kiln to re-fire, the price will return to the original color.

As early as the Ming Dynasty, master alabaster craftsman Chen Zhongmei already used the methods of sand blending and sand paving to enhance the decorative effect on the surface of alabaster wares.

Sand mixing process

In the processed clay or powder, according to the requirements of a variety of sandy particles with a certain size and proportion, in order to improve the density of particles.

Sand laying process

The transferred particles and the base mud belong to the same kind of mineral material, known as the color-toned sand; transferred particles and the base mud does not belong to the same kind of mineral material, known as the different color-toned sand.

This color sand into the original mud, due to the same nature of the mud, after firing, the tire color will not produce large changes, but the particles in the mud content has increased, mainly play a role in strengthening the skeleton of the billet. For some of the softer particles, particles also need to be 600-800 ℃ firing to increase the strength of the particles, otherwise the particles in the molding process is easy to be crushed by the tool and caused by the surface of the vessel trailing phenomenon.

If most of the Zhuni clay shrinkage and deformation rate are relatively large, not conducive to the production of large works alone, need to rely on the method of sand to increase the strength of the blank, so that the blanks after the firing of the overall shrinkage and deformation to reduce, improve the rate of finished products fired. Therefore, most of the modern Zhuni pots are mixed with coarse sand particles or supported by clinker (clinker is the powder that is ground into the finished clay after firing).

Different color sand will produce different color effects depending on the color and texture of the particles and the base clay. If the transfer of particles into the hard nature of the particles, after firing, the surface of the ware particles protruding, coarse pear skin; when the transfer of particles into the soft nature of the particles, after firing, the surface of the ware will produce a fine concave point. The softer the particles are, the more pronounced the dots are, creating a textural effect like orange peel.

Sand Paving

Sand paving refers to the process of making Zisha blanks, the sand grains of different clay colors are paved, dotted and sprinkled on the surface of blanks that still have a certain degree of humidity. And then with the help of tools will be embedded in the surface layer of the blank. The sand mainly plays the role of decorative embellishment, so that after the firing of the surface of the purple sand ware into the sand point and the tone of the tire to form a sharp contrast effect.

The texture of the sand particles is generally required to be higher than or equal to the texture of the blank particles. If the texture is softer, it will cause the particles to drag during the production and after firing due to the shrinkage of the particles and the incompatibility of the tire texture.

Sand extraction process

Sand extraction is to separate a certain portion of the specification of the particles in the processed powder or slurry. The extraction of 60-80 mesh particles from 40 mesh powder allows the remaining particles to be fired with the fines to create a distinct contrasting effect of coarse and fine, resulting in a new texture.

The characteristics of zisha pots

First, zisha pottery is hammered from the sand pottery: neither take away the aroma of tea nor cooked soup gas, so used to make tea color and aroma are embedded.

Second, the sand teapot can absorb tea: use for a period of time can increase the accumulation of "tea rust", so the empty pot into the boiling water also have tea.

Third, the special material of zisha kettle makes the pot breathable, so that the tea does not lose its original flavor, with the characteristics of the summer more than overnight not rancid.

Fourth, easy to wash: not used for a long time, it is inevitable odor, can be used to soak in boiling water two or three times, and then pour away the cold water, and then bubble tea original flavor unchanged.

Fifth, hot and cold adaptability: cold winter months, injected into the boiling water, not due to rapid changes in temperature and cracking; and sand heat transfer is slow, no matter whether to mention the grip are not hot.

Sixth, alabaster ceramic burn-resistant: placed in the winter warm fire tea, the pot is not easy to crack. When Su Dongpo with alabaster ceramics tea kettle, there is a "pine wind bamboo stove, kettle call" verse, is not by chance. This is the ancient and modern tea drinkers, so especially favorite reason for the use of zisha pots.

Seventh, Yixing zisha pot plasticity;

Eighth, Yixing zisha pot drying shrinkage rate is small;

Ninth, zisha clay itself does not need to be added with other raw materials can stand alone into ceramics; the finished product of Yixing zisha pot pottery has a double pore structure;

Tenth, Yixing zisha pot molding does not need to apply glaze. Zisha ware inside and outside are generally unglazed, to pure natural texture and texture for the beauty. Zisha teapots have a variety of shapes, including simple practical shapes and strange and bizarre shapes, but in general, they are divided into the following categories: geometric, natural (flower-vegetated), sinewy and horizontal pots and teaware.

Source:Baidu Encyclopedia-Zisha Pot