Chapter 1228: Simple does not mean easy to identify
The method of using hand dishes to remove the flames of porcelain is time-consuming and labor-intensive, and requires careful attention. It is definitely rare now.
After all, modern people are eager for quick success. Who would spend months on a piece of porcelain?
However, if a master really does this, ordinary people really can't identify it.
And the old porcelain produced in this way must be of high value!
For money, what kind of price can modern people not pay?
Therefore, there is a faster way to make it old.
If you want to achieve better results faster, use water grinding to remove the flare.
Place the utensils under constantly flowing water and rub the glaze with the flowing water to eliminate the "fire".
If you want it to be more refined, use the oil grinding method.
First, gently rub it with a pulp weight, then use a cowhide rubber rudder, and rub it with oil to eliminate fine marks and make the glaze surface smooth and moist.
If your mind is a bit poisonous or crazy, use the acid leaching method.
Because the glaze of ceramics is silicate, it forms a transparent glassy glaze with beautiful luster.
Soaking porcelain with acetic acid, hydrofluoric acid, nitric acid, oxalic acid, etc., which can react with silicates, can cause glaze corrosion.
This can also make the glaze dim and appear turbid, thereby eliminating the "fire".
Some do not soak, but directly use a rag dipped in acid and repeatedly wipe the glaze surface to achieve the desired effect.
The disadvantage of this method is that the acid corrodes the glaze too strongly, causing the glaze to become devitalized, dull in luster, or even opalescent.
This is very different from the "clam light" that naturally forms over time.
Under a high-power magnifying glass, countless small holes corroded by acid can be seen.
Why do you say it's a bit crazy to do this? It's because these corroded holes are destroying the porcelain and killing the goose that lays the egg.
Of course, there are also compromise methods, such as the mixed dipping method.
This involves mixing several solutions together.
For example, soak with acetic acid and then use tea water, plant ash water, etc.
This will not only eliminate the "flame", but also create various stains that people mistakenly think are caused by long-term use.
After being treated with acetic acid, the residues of glazed pottery and porcelain with high water absorption are easily absorbed by the matrix.
Washing the surface of the utensils with hot water will emit a bitter smell.
There are methods like this that use chemicals to make things look old, and there are also oxidation methods.
Use potassium permanganate, a strong oxidizing agent, to oxidize the glaze.
Except for the slightly reddish surface, the other characteristics are consistent with those after acid leaching treatment.
Rinse the utensils with water. If you use too much potassium permanganate, the water will turn purple.
Sometimes if you dip your fingers in some water and touch them, your fingers will be dyed purple-brown.
In fact, this is not the biggest flaw. Among the old techniques for removing flames, there is another simple method, which is to apply oil stains.
Just use a sponge to dip the oil stains inside the range hood in the kitchen and apply it on the ceramic surface.
Wipe it clean after an hour and repeat the operation several times to make the ceramic glaze matte.
There are no signs of wear and tear, and the cost of this method is very low.
The matting agent matting method is to add a certain proportion of zinc oxide, zirconium oxide and other matting agents to the configured glaze, so that it can achieve twice the result with half the effort.
Using energy dispersive x-fluorescence analysis, as long as the content of certain metal oxides in the glaze of an artifact is found to exceed the normal value, it can be concluded that it is a modern imitation.
There are many ways to make things look old. Although Chen Wenzhe knows them all, he has not used many of them.
For example, the soil burial method is to bury new porcelain in fine mud, then take it out and wipe it off with a dry cloth after a few days. After doing this several times, you will see that the glaze has a yellowish old color.
High-pressure cooking is to use tea and a little alkali to boil the porcelain for a long time to remove the shine.
In recent years, some people put new imitations into a pressure cooker to cook them, which can also achieve the purpose of making the glaze lose its luster.
There is very little rust on porcelain after the Ming and Qing Dynasties. The main targets for rust are ceramics unearthed far back from this era.
There are several methods, the first is the spreading method.
Use a brush to dip an appropriate amount of diluted nitrocellulose varnish and apply a thin layer on the areas to be rusted.
If the scale appears to be sagging, dip the material in the liquid until it is saturated to form traces.
When it is still wet, spread talcum powder or other extender pigment powder on top.
After drying, just remove the floating powder.
When making rust, you can also add other pigments or sprinkle a little loess and make it at the same time as soil rust.
Although they look very similar on the surface, you can tell the authenticity by scratching them with a knife.
The second is the metathesis method. Apply a layer of sodium silicate aqueous solution to the area that needs to be rusted. After the coating is dry, brush the surface of the coating with 5% dilute hydrochloric acid.
When hydrochloric acid meets sodium silicate, a metathesis reaction will occur and a white salt substance will be generated.
Finally, rinse the following rusted areas with clean water to remove unreacted chemicals and excess salt.
Then there is the soil burial method, where the imitation pottery is buried in loess rich in groundwater.
After burying it for several months, take it out to dry and repeat it several times to develop soil rust.
The effect is particularly good if it is buried in an ancient pottery firing site or in an ancient tomb.
The disadvantage of this method is that the rust is still young and is not tightly integrated with the pottery. It will fall off if you scratch it lightly with your fingernail or a knife blade. This phenomenon will never occur with real rust.
In fact, in terms of convenience and speed, the heating method is the simplest.
This method is to heat the pottery, and then mix the soil from the ancient pottery site or ancient tomb with alum and apply it repeatedly while it is hot.
Repeat this until the color is no different from the original color.
This method also has the disadvantage of not being tightly bonded. In addition, if it is washed with alkaline boiling water, all the rust will fall off.
The more troublesome thing is the mud coating method, but of course, the effect is very good.
This involves putting soil into special Chinese medicine, boiling it for 20 hours, and then applying the resulting mud to the ceramic surface.
The soil rust treated in this way is very similar to the unearthed soil rust, and is closely integrated with the ceramics. Even if it is scraped with a sharp blade, it will not fall off easily.
In addition, there is also the clay method.
First, mix the ceramic glass glue and soil into a viscous consistency and apply it on the ceramic surface.
Then heat the burning newspaper and slap it on the ceramic surface.
The rust produced is closely combined with the pottery, and the black paper dust will penetrate deep into the soil, making it even more obvious the traces of time.
Because of the presence of glass glue, the smell of burning glass glue will emit when exposed to high temperatures.
For the coloring method, first apply shellac paint twice on the surface of the pottery, then soak the pottery with shellac paint and mineral pigments to create a background color, and finally apply bletilla striata juice on the surface to create rust.
Once the pottery made by this technique is put into hot water, the traces of forgery will be clearly visible.
As for repairers and splicers, the rust at the joints will not condense into the original parts. It is not difficult to see through them if you carefully identify them.
However, to see through it, you have to know that there is a way to make it look old.
Chen Wenzhe knew many simple old-fashioned methods that are still used by people today. Why?
Isn’t it because many people in the market are ignorant?