My system is not decent

Chapter 1087 Fine-tune the formula

Copper and iron often play a key role in firing porcelain, especially in the process of glaze color development.

But in malachite green glazed porcelain, copper is the key, not iron.

Malachite green glazes in ancient China generally only contain a small amount of ferric oxide, and the content is less than 1%, which has little effect on the glaze color.

Modern research has proved that the malachite green glaze fired in the north before the Qing Dynasty also contained a large amount of lead and a small amount of tin dioxide as an opacifying agent.

The results of chemical analysis showed that the presence of tin dioxide was related to copper.

In malachite green glazes before the Qing Dynasty, if the copper content in the glaze is high, tin will generally appear, and vice versa.

This shows that the tin may have been brought in by using the copper oxide slag produced during the smelting of bronze as an ingredient, rather than adding it on purpose.

Bronze is a copper-tin-lead alloy. In the Qing Dynasty, because the production of bronze was replaced by brass and red copper, the slag produced during the smelting of brass and red copper was mainly copper oxide and contained no tin. Therefore, no tin was found in the results of chemical analysis.

As mentioned above, the malachite green glaze is sometimes a bit bluish, and it is generally believed that the blue color is caused by cobalt oxide.

However, the results of chemical analysis show that, except for some purple-blue fahuacai fired in the early days in the north, which contain about 0.6% cobalt oxide, most peacock blues do not contain cobalt.

In addition to cobalt oxide, the early fired purple-blue fahuacai also contained a small amount of manganese oxide, which was caused by using cobalt ore as the source of cobalt oxide.

Malachite green glaze is colored by divalent copper ions and must be fired in an oxidizing flame at a firing temperature of 950~1000°C.

After researching this, at least malachite green glaze and peacock blue glaze will not worry about the failure of firing.

What's more, Chen Wenzhe also watched the whole process of firing the official kiln porcelain with peacock green glaze in Qing Dynasty.

Knowing how to mix and use different raw ore materials, it is impossible to say what effect will be achieved in the end.

In addition, the effect brought about by the final kiln firing process is definitely different.

So, this time I still have to try burning.

To try burning, you need to try to do more first, so that you can know what kind of effect you will get under various circumstances.

Do more, not just do it casually. This time, Chen Wenzhe plans to imitate all the best ancient porcelains as before.

As for peacock blue glazed porcelain, the best firing must have been during the Ming and Qing dynasties.

This kind of colored glaze was already produced in the Xuande period of the Ming Dynasty. Malachite green was more famous in the Zhengde Dynasty, and the firing of this glaze was very popular in the Kangxi Dynasty in the Qing Dynasty.

The green glaze ware of Guangxu Dynasty enjoyed a high reputation in the late Qing Dynasty, including malachite green, melon skin green, turquoise green and so on.

Among them, the types of peacock green glaze are mostly stationery utensils such as cone-shaped bottles, skimming bottles, Guanyin bottles, Tianqiu bottles and washers, as well as ornaments such as lions and parrots.

Chen Wenzhe can do some of these things, especially decorations. It turns out that Chen Wenzhe really hasn't done much.

It's just that he had learned glass-shaped ornaments before, and now it seems that it is not difficult to make porcelain ornaments, or malachite green-glazed porcelain ornaments.

No matter how difficult it is, it is best to start with simple shapes for any new type of porcelain.

After all, it is a trial firing to see how the color of the final firing is, so in the beginning, in order to pursue speed, it is best to make dishes.

Of course, the bowls and dishes were not made casually. Chen Wenzhe first imitated several peacock green glazed bowls from the Zhengde period of the Ming Dynasty.

As for why, could he still say that Zhang Gu made bowls too fast, as long as he had a little idea on his side, he would start researching and supplying embryos.

Since there are embryos on site, he still has to take the trouble to make it himself?

The peacock green glazed bowl must be a kind of low-temperature colored glaze with emerald green and translucent color, resembling peacock feathers.

Because copper is used as the coloring agent, there are two types of glaze color, deep and light.

Here, you need to grasp it by yourself, which is also the purpose of trial burning.

Pick up a bowl embryo, feel it with your fingers, the wall is smooth and even, the texture is hard, and the strands are not bad.

This kind of peacock green glazed bowl is also easy to make. After all, it has a skimming mouth, an arc wall, a thin bottom, and a round foot, and it doesn't need to be written.

The inner wall of the bowl and the inner ring foot are covered with blue-white glaze, the outer wall is covered with malachite green glaze, and the pattern of upturned lotus petals is darkly drawn near the foot.

Although this bowl has not been signed, its typical Zhengde palace bowl shape and the feature of light green and white glaze on the inside of the vessel's feet can all indicate that it is a Zhengde official kiln.

The firing of peacock green glazes in the Zhengde period of the Ming Dynasty reached its peak. Therefore, if the imitation firing is to be successful, the color of the firing must be green and bright.

These peacock green glazed bowls are not small, they are all 6.6cm high, 16.2cm in diameter and 6.5cm in foot diameter.

It was done smoothly, and Chen Wenzhe made all the glaze recipes he could think of.

A bowl, a glaze formula, anyway, it is made quickly, and it can be fired in a kiln after a little drying, and the result will be completely clear the next morning.

After the firing results of this batch of bowls come out, he will then fine-tune the recipe based on his inheritance experience to get what he wants.

In this way, originally he only planned to make three peacock green glazed bowls, but in the end he made more than a dozen.

These bowls use different proportions of glazes, so if they are fired according to the method of malachite green glazed porcelain, what kind of green color will appear in the end can only be known after the firing is completed.

After finishing these bowls, Chen Wenzhe didn't think too much, and just made the dishes directly.

The small dish is simpler than the plate, but now Chen Wenzhe has to increase the difficulty, the glaze ratio is adjusted relatively large, so this time I made a light green glaze dark flower Chi pattern cup and saucer

.

Although copper is still used as the coloring agent this time, the final result of firing is not necessarily light or rich in color.

It doesn't even have to be green, maybe it's red glazed porcelain.

The glaze formula is not precise enough. It is possible that it may be copper red glaze, purple glaze, or even blue glaze after firing this time. This depends on the temperature control inside the kiln.

In any case, there is no way to accurately obtain the malachite green glaze anyway, so he simply imitated the Qing Kangxi's light green glaze dark flower Chi pattern cup and saucer.

In the end, if the color is right, it is malachite green glaze, if it is not suitable and the color is too light, it is light green glaze.

If other colors appear, it means that the firing has failed.

And the price of failure is just a cup, or a butterfly, or at most a set of cups and saucers.

Because this is a set of porcelain, called cups and saucers, cups and saucers are combined into a set.

The height of the cup is 3.5 cm, the diameter of the mouth is 5.7 cm, and the foot diameter is 2.4 cm;

The dish is 1.6 cm high, 12.7 cm in diameter, and 10 cm in foot diameter.

It's not big, it's not complicated, and it's simple to make.

The mouth of the cup is slightly skimmed, the belly is deep, the feet are circled, and the ears are placed symmetrically on both sides.

White glaze is applied inside and light green glaze is applied outside.

Four chi tigers are secretly engraved on the outer wall, and the blue and white "Kangxi Years of the Great Qing Dynasty" double-line six-character regular script is signed on the outer bottom.

The dish has a skimming mouth, a shallow arc wall, and a circle foot.

The inner bottom of the dish has a circle of protrusions, which can hold the cup foot when placing the cup, and the center of the dish is darkly drawn with two chilong patterns.

White glaze is applied to the inside of the foot, and the blue and white "Kangxi year system of the Qing Dynasty" double-line six-character regular script inscription is also signed on the outer sole.

(End of this chapter)