Is JianZhan open piece a defect? Here's the answer

by zhangJackson June 7, 2022

After buying a JianZhan, many of you may have "small cracks" in the glaze, either new to you or after a period of time.
Many friends who do not know much at this point will often cry out: "I fell for it, did I buy a fake JianZhan?

Many people often have this question, JianZhan open piece is defective damage?

Here we can give you a conclusion: JianZhan open piece is not a defect, does not affect the overall appearance, and may even be the icing on the cake.

The so-called open piece, also known as ice cracking, is a natural cracking phenomenon on the glaze of porcelain.

Why JianZhan is not a flaw, does not affect the overall appearance, and may even be the icing on the cake. There are three reasons.

1、Open flake is a natural formation on the glaze of porcelain is not completely cracked phenomenon.

2、The unique texture effect formed by open flakes, also known as "ice cracking". Some kilns are beautiful with open flakes, typically represented by the Song Dynasty's Gao Yao and Guan Yao.

Porcelain is a long process, although most of the porcelain in the formation of open pieces have ended, but the speed of the later open pieces is much slower, even up to 10 years, just bought porcelain with open pieces this is the normal process of porcelain open pieces.

3、Jian kiln is not deliberately pursuing open flakes, but other kilns porcelain open flakes do not affect the integrity of the glaze, JianZhan open flakes are also the same.

To sum up
The open flakes are visually "cracked", but macroscopically they are not cracked and do not affect the integrity of the porcelain.

Open pieces of the calendula, the interior of the body is intact, and affect the integrity of the object "punch line" (punch line that porcelain received the impact of the formation of cracks) is essentially different; and raw firing products "shrink glaze" phenomenon is also essentially different; some glaze of the open pieces, and even increase the calendula The beauty of the JianZhan.

So how are the flakes formed?

1、The forming structure of lime glaze, a very important criterion for judging porcelain is the silica content ratio.

Silicon dioxide is one of the main components of all porcelain glazes, and often the only acidic group, the introduction of calcium oxides and other alkali metal oxides through the glaze ash is present as a basic group.

The proportion of the deployment of acid and alkali groups will also cause different glaze expansion, naturally open flakes.

2、The glaze of JianZhan is a crystalline glaze with a relatively thin glaze surface, which is used more frequently as a tea vessel, and the ensuing thermal expansion and contraction is frequent, so it is normal to have flakes.

But how long does it take for a JianZhan open piece to appear?

There is no certainty as to when JianZhan open pieces appear. Some new marigolds have open flakes, and some open flakes appear during use.

JianZhan glaze is a crystal glaze, glaze glass surface is relatively thin, and we get into the JianZhan after the hot tea, the use of frequent, that is, thermal expansion and contraction is also frequent, open flakes is not normal.

What's more, JianZhan is a black porcelain, such as in the sun or light, look extra obvious.

Therefore, we have to be prepared before buying JianZhan, some of those characteristics symbiotic with the JianZhan process, we have to have a tolerant mind, such as some open pieces, small air holes, genetic glaze, etc..

People mastered the law of open piece and made open piece glaze, which became a special decoration of porcelain. In the Song Dynasty, Ru, Guan and Ge kilns all had such products.

According to the color, it can be divided into eel blood, gold wire, light yellow caviar pattern; according to the shape, it can be divided into net pattern, plum pattern, fine broken pattern, etc.

JianZhan open pieces and other porcelain in fact, it is the same, so there is no problem, and does not belong to the defective products, it is a traditional process of natural presentation of the results, respect for nature is perhaps the most open mind, appreciate JianZhan is to cultivate an open and tolerant mind, which is to enjoy the process, do you think?