Yixing Zisha Series: Zini — The Clay Which Made Yixing Famous

Last Updated: 2020-07-28

Overview of Zini (紫泥 – Purple Mud/Clay)

Zini (紫泥) is the most popular and the most common of all Yixing Zisha. It is the original clay which gave Yixing its fame, centuries ago. In the ancient times Zini (紫泥) have also been called Qingni (青泥/Greenish Blue Mud/Clay). Some notable variants that we’ll talk about are Dicaoqing (底槽清), Qinghuini (青灰泥) and Tianqingni (天青泥).

If you want to know more about the kinds of Yixing Zisha Clays then click: [HERE]

Zini Ore (紫泥) from Taixi Mine (台西矿区), and its colors after firing
Zini Ore (紫泥) from Taixi Mine (台西矿区), and its colors after firing

Zini got its name from the color of the fired clay, which is usually composed of various shades of brown and purple.

It has good plasticity, high strength, low shrinkage during firing, and generally good performance through the whole process of making a teapot. Because of its ease-of-use, it became the most popular material during the dynasties, allowing historical potters to make many of the famous shapes and designs that are still common to this day.

Furthermore, because of Zini’s porous structure, it could greatly improve the taste of low-quality tea the common people drank in those times.

Di Cao Qing (底槽清)

Dicaoqing (底槽清) is probably one of the most well known subcategory of Zini. It is a special grade of the Zini Ore. Before Industrial mining, people dig trenches into the ground, to find Zisha ore, and Di Cao Qing would be found at the bottom of the trench, this is how it got its name (Di/底 Cao/槽 – Bottom Trench).

Dicaoqing was first found in larger quantities in the famous No.4 Mine(四号矿井) at Huanglongshan(黄龙山). Later it was also found in No.5 Mine(五号矿井) and Taixi Mine(台西矿区). 

Dicaoqing in its raw form could be easily identified by the greenish 1-5 cm sized dots on it (which are referred to as “Chicken eyes”), besides the usual Zini Ore attributes. The older the Dicaoqing Ore the smaller the diameter of the dots, and the older the Ore the bigger the Firing Range and smaller the Shrinkage Rate is.

Dicaoqing Ore (底槽清) from Taixi Mine (台西矿区), and different colors after firing
Dicaoqing Ore (底槽清) from Taixi Mine (台西矿区), and different colors after firing

Because of the wide Firing range of Dicaoqing it can have a large variety of colors after firing. Brownish Orange, Brown, Dark Brown, Dark Grey Brown. 
The following attributes depends on the age of the Ore and which mine it came from.

Shrinkage Rate: 3.5% — 5.5%
Firing Temperature: 1180°C — 1250°C
Porosity: Between Zhuni and Duanni

Dicaoqing is the gold standard of Zisha, which made Yixing famous.
It allowed craftsmen to make exquisite teapots, in a wide range of colors.
It can quickly develop a beautiful patina and shine, which deepens the color of the teapot.

Dicaoqing can be used for any kinds of tea, because it keeps some aroma while also decreases bitterness and astringency, making it a really good all around clay, which can improve on any tea where the loss of some aroma is acceptable.
If you only plan to get one Yixing teapot, let it be this one.

Further reading materials: Mud and Leaves article about Di Cao Qing

Qing Hui Ni (青灰泥)

Among non Chinese speakers, Qing Hui Ni (青灰泥) could be confused with Qing Shui Ni (清水泥), but they are totally different. The first is an actual Zisha ore while the latter isn’t. 

Qinghuini was common and popular during the late Ming and early Qing Dynasty. In the modern times however it’s often a forgotten type of Zini. It is also called Shayupini 鲨鱼皮泥 or Shark Skin Clay, due to how the surface of the teapot feels to the touch, after firing. 

Qinghuini (青灰泥) from Dashuitan (大水潭), and colors after firing
Qinghuini (青灰泥) from Dashuitan (大水潭), and colors after firing

It is originally found Mainly in Dashuitan (大水潭) mining area being the second most prized Zini variant after Tian Qing Ni. However it could also be found in the south part of Huanglongshan, close to Dashuitan.
Compared to other Zini it contains more sand like particles. After firing it has a grayish-brown color and has the following attributes:

Shrinkage Rate: 6%
Firing Temperature:  1180°C — 1220°C 
Porosity: It is more porous than Zhuni, but less than Duanni, similar to other kinds of Zini.

Qinghuini, is also quite versatile and so can be used with any kinds of tea. It is worth noting, that a new Zini teapot at the beginning could be more muting, but with seasoning and time it’ll adopt to the tea you use it with.

I’d recommend Qinghuini for people who want to experience what teapots during the Ming and Qing dynasties have been. I’d also advise to get a teapot with a more classic, traditional shape, to go along with the feeling.

Further reading materials: Mud and Leaves article about Qing Hui Ni

Qing Shui Ni (清水泥)

Qingshuini is one of the most loosely defined “clay” among Yixing Zisha, and one which can cause a lot of confusion. The reason being, that Qingshuini is not an actual Zisha ore, but it’s a phrase which potters used during the factory era to refer to clay, which has not been altered. Meaning that after crushing the ore no other materials, chemicals or coloring oxides were added to the clay, so it’s pure Zini. Qing Shui (清水) means Clear, Water, which explains the meaning, that the Ni (泥/Mud, Clay) was clear, pure, unadulterated Zini.

Because most Qingshuini Zini teapots during the Factory era were light brown in color, people started to use the word to refer to teapots with similar texture and color to those Factory 1 teapots. This is what created the confusion that exists today.
So if you see Qingshuini mentioned in case of a modern teapot, then be wary, because it doesn’t tell anything about what the teapot is made of, only what it tries to be (a light brown colored teapot).

Lao Zini (老紫泥)

Lao Zini is not an exact term. Some people think, that since Lao (老) means Old, then Lao Zini means Zini, that has been aged for a long time, like 20-30 years or more. However Yixing potters use the term Lao (老) with different meanings, so if you buy a teapot directly from the Artist, make sure to ask what they mean by Lao (老). Usually there’s two things that Lao (老) could mean.

Raw Zisha ore has to be weathered, processed and then aged for some time to reach the necessary viscosity and plasticity. This time is different for each Zisha ore, but usually the longer the clay has been aged, the better it is for making a teapot (Easier to form into shapes and smaller chance of breaking during firing). 

Therefore Lao Zini could refer to Zini which have been aged longer than usual, the average time being around 3-6 month. Aging Zini for a couple of years can increase its durability during firing, which allows it to be fired at higher temperatures. Firing at higher temperatures makes the teapot have a darker color, so that could be a reason why Lao Zini teapots seems to be a darker brown/purple than other Zini teapots.

Another meaning of the term Lao (老) is that the clay was processed with old, traditional techniques, without the help of modern technology. Using traditional clay processing techniques results in a teapot with more “flaws”, meaning more sand and black iron particles in the clay, which gives a less smooth surface to the teapot. These attributes are undesired in the eyes of Chinese customers, so it’s difficult to find such teapots.  

Tian Qing Ni (天青泥)

Tianqingni (天青泥) is a Legendary Zisha. It was the most prized clay of the Ming and Qing Dynasties, and was already rare during those times. Many potters dream is, to work with it in their life. 

It’s frequently translated as Reddish Black or Sky Blue Clay, however if we consider, that in ancient times they called Zini (紫泥) Qingni (青泥), then it could also be translated as Heavenly/Sky Zini, which would reflect its Legendary status. 

Tianqingni (天青泥) Teapot made by Yang FengNian (楊鳳年), in the Yixing Ceramics Museum
Tianqingni (天青泥) Teapot made by Yang FengNian (楊鳳年), in the Yixing Ceramics Museum

There are two known Yixing Zisha teapots which are made of Tianqingni. One of them is located in the museum of Nanijing and the other is at the Yixing Ceramics Museum. Both teapots are made by Yang FengNian (楊鳳年), who was the most famous female Yixing Artist and lived during the Qing Dynasty (around ~1800-1850).

Tianqingni was originally mined at Da Shui Tan (大水潭) which is a ~100m away from Huanglongshan. The mine got flooded at the end of the Qing Dynasty and as the name suggest is a small lake now. Therefore mining is impossible, and the lake is now surrounded by roads and houses.

The Legendary Tianqingni (天青泥) from Dashuitan (大水潭), and its colors after firing
The Legendary Tianqingni (天青泥) from Dashuitan (大水潭), and its colors after firing

Since it’s an ancient type of Zini, there are lots of conflicting materials about this clay. It adds to the confusion that no one lives who was able to see the real raw ore from Dashuitan, so there are various kinds of Zini on the market labeled as Tianqingni (Even chemically colored blue teapots).
However one thing where there seems to be a consensus, is that it has a Dark liver color after firing (personal note: So I think Reddish Black Clay is a good translation). Besides a dark liver color, it also has the following attributes:

Shrinkage Rate: 8%
Firing Temperature: 1160°C — 1210°C
Porosity: Unknown, but it can be assumed that it’s in range with other kinds of Zini, and I’d assume it to be similar to Qinghuini.

Since it’s a Zini it should perform with tea similarly to Di Cao Qing or Qing Hui Ni. 
If you have an authentic one, then congratulations, and send me a message 😀 
It’s the most prized and wanted of all Yixing Zisha, while being the rarest. A verified Tianqingni teapot from Dashuitan won’t be 200$ and neither 500$ nor 1000$.

Sources:

  • Yixing Zisha Mineral by Zhu Zewei – 宜兴紫砂矿料 by 朱泽伟
  • Pictures were taken by me from the China Yixing Ceramics Museum 中国宜兴陶瓷博物馆
  • Further information were collected from various Chinese online articles on topics where there were consensus about certain matters
  • https://news.taohuren.com/zishaniliao/2017-05-17/article-157976.html