The real malachite green glaze is a low-temperature glaze with copper as the colorant.
It originated from the Song and Yuan folk kilns, and was first seen in the Cizhou kiln of the Song Dynasty.
During the Chenghua period of the Ming Dynasty, the Jingzhen kiln was mature for firing.
There are two firing methods. One is to use the plain body to directly glaze and bake. The glaze is easy to peel off;
The second method is to cover the white glaze ware with glaze before firing, so the glaze will less likely peel off.
However, in the early days, the glaze was directly applied to the blank and fired at low temperature in the kiln.
Therefore, the product is thicker and the glaze is easy to peel off.
It was not until the establishment of the official kiln system in the early Ming Dynasty that malachite green glaze firing entered a new stage.
The firing process is not difficult to say. Generally, a white glaze is applied on the formed plain body first, then fired in the kiln at high temperature. Then the malachite green glaze is applied on top of the white glaze. After a second low-temperature firing, the glaze becomes colored.
bright,
It is rare to see glaze peeling off.
Of course, this already requires a high level of craftsmanship.
An unknown work from the Qing Dynasty, "Nanyao Notes" said: "Falan and Facui are two colors that were only found in Chengdu kilns in the old days, and jadeite is the best."
In other words, people in the Qing Dynasty also believed that malachite green glaze was fired during the Chenghua period of the Ming Dynasty.
However, judging from the handed down products and unearthed objects, it was already fired during the Xuande period, and continued to be fired during the Chenghua, Hongzhi, Zhengde, and Jiajing dynasties.
Of course, the malachite green glaze is quite similar to the green on peacock feathers, which also confirms the metaphysics that blue is green and green is blue. The real malachite green glaze has such stunning beauty!
At this point, you must pay attention when firing, because if you are not good at firing malachite green,
But it burned into peacock blue.
certainly,
The emergence of malachite green,
It must be because of the peacock blue.
At that time, peacock blue porcelain was fired, but accidentally, malachite green was fired. This is how bizarre the world is.
There are two shades of malachite green glaze: the darker one is emerald green, and the glaze color is bright and gorgeous;
The lighter ones are mainly used in colored glazes, such as eggplant purple and other glazes, often with malachite green.
If malachite green is applied to blue and white, the blue and white will turn black.
The malachite green glaze fired in Jingzhen in the Qing Dynasty reached the highest level in history. It has three important features in appearance.
The first important feature is the green and bright glaze color, which is extremely rare among ancient Chinese ceramic glazes.
There were many varieties of green glazes colored with copper in ancient China, such as the green glazes of Tang Sancai, Qionglai Kiln and Shachang Kiln.
They all come in different shades, but none compare to the malachite green glaze.
Some malachite green glazes have a blue tint in the green, which some people call "peacock blue". It is generally believed that the blue color is the result of cobalt. The results of chemical analysis show that most of the malachite blue has nothing to do with cobalt.
The second important feature is that the glaze layer is clear, with few bubbles, crystallization and unmelted glaze.
For example,
At the Jiudelou Exhibition, a peacock green glaze plum vase with lid from the Kangxi period of the Qing Dynasty was on display.
Just one example.
The third important feature is that the glaze is densely covered with fine caviar-sized slices, which is very distinctive.
Anyone who studies ancient ceramics knows that the glaze color of ceramics is related to many technological factors.
When it comes to craftsmanship, there are many aspects involved.
The first is the type and concentration of the colorant, followed by the firing atmosphere, firing temperature and glaze layer thickness.
Chen Wenzhe only knew about these before, but was not familiar with them.
But it doesn't matter, if he wants to learn, he can do it.
Therefore, in just an instant, a large amount of knowledge poured into his brain.
But this time, it poured into his brain systematically, making him learn faster and more conveniently.
The Sui Marquis Pearl is indeed easier to use. It can accurately push the inheritance knowledge according to Chen Wenzhe's needs.
Just like this time, when he wanted to learn the manufacturing process of malachite green glazed porcelain, Sui Houzhizhu accurately sent him a batch of professional and relevant information.
In just one moment, Chen Wenzhe received a lot of useful moments.
The most special thing among them is actually some modern chemical analysis, which can also be obtained on ancient porcelain pieces?
Although he felt very confused, Chen Wenzhe had no intention of rejecting the knowledge related to malachite green glaze. As long as he dared to give the Sui Marquis the Pearl, he would dare to learn it.
As for where all this knowledge comes from, it really doesn't matter.
"Civilization inheritance system, I have forgotten this name!"
After receiving a large amount of knowledge inheritance, Chen Wenzhe laughed.
The external manifestation of Sui Hou's Pearl, or in other words, when we first came into contact with him, it was displayed in front of him in a systematic way.
Since it is a civilization inheritance system, it naturally has the inheritance of many civilizations?
These are not important. What is important is that these cultural inheritances should be helpful to Chen Wenzhe.
Colorant? Co-solvent? The ancients must not have understood these terms.
However, although they do not understand these terms, they definitely know how to use them.
As a modern person, Chen Wenzhe knows very well that the chemical composition of the flux also has a great impact on the color development of the colorant.
The green and bright glaze color of Chinese malachite green glaze is not only related to the large amount of divalent copper ions contained in the formula, but also closely related to the large amount of potassium ions.
The malachite green glaze of the Qing Dynasty in China is a high-alkali glaze with a high potassium content prepared from saltpeter and quartz sand.
If lead oxide, feldspar, plant ash or other fluxes are used instead of nitrate, other conditions remain unchanged, and the tone of malachite green cannot be produced anyway.
The green glazes of Shachang Kiln and Qionglai Kiln are the best examples.
Although they are also colored with divalent copper ions, they are not high-alkali glazes, and they also contain a small amount of opacifying agents tin dioxide and phosphorus pentoxide.
Therefore, it is impossible to burn out a hue like malachite green.
The malachite green glaze in Persia and Iraq does not have a high potassium oxide content, but a high sodium oxide content.
Potassium oxide and sodium oxide are both alkali metal oxides. Their chemical properties and molecular structures are quite similar, so they have similar effects on glaze color.
Potassium oxide is a strong flux. If the dosage is high and the firing temperature is high, the high-temperature viscosity of the glaze will become very low.
In this case, all the bubbles in the glaze layer will run away, and granular glazes such as quartz will all melt into the glaze, making the glaze completely vitrified.
The complete vitrification of the glaze, coupled with the presence of a large amount of divalent copper ions and the white porcelain body, results in a green glaze with a clear and bright glaze, just like jade, which is very cute.
In this way, if copper is used as a color agent, the result will be malachite green, not peacock blue.
Therefore, the main colorant of malachite green glaze is copper, and the copper content is very high.
These are key technical skills. If you don’t understand these, you will never be able to make good malachite green glaze porcelain.
For example, the malachite green glaze porcelain of the Cizhou kiln in the Song Dynasty had a copper content of 5.6%, the Ming Dynasty festoon ranged from 3.4 to 5.2%, the Qing Dynasty malachite green was as high as 9.0%, and the Persian pottery unearthed in Yangshi had a malachite green glaze of 2.5 to 3.7%.
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The high copper content helps the glaze color become more verdant.
Pay special attention here. Iron is also the key to the color of porcelain. If there is too much, there will be conflicts.