Overview of the ”Magical“ Yixing Zisha Clay

Last update: 2019-10-18

Introduction to Yixing Zisha (宜兴紫砂)

Yixing Zisha (紫砂) — Purple (Zi/紫) Sand (Sha/沙) — is the umbrella term for all raw clay materials found around Dingshuzhen (丁蜀镇), a town near the city of Yixing (宜兴), in the Jiangsu (江苏) province of China. Most Zisha comes from a particular place, called Huanglongshan (黄龙山), aka the Yellow Dragon Mountain. Yixing Zisha from this area is usually identified with the prefix “Benshan (本山)”, which means “Original Mountain”.

You can find Huang Long Shan with: Baidu Map HERE

Huang Long Shan (黄龙山)
Huanglongshan (黄龙山)

The Main Categories of Yixing Zisha

The names for each type of Zisha have unique origins. Most of the names come from the color of the clay after firing. These include some of the main categories of Zisha, like Zini (紫泥/purple clay), Hongni (红泥/red clay), and Zhuni (朱泥/vermillion clay). An exception to this is Lüni (绿泥/green clay), which refers to the color of the raw material. (personal note: In my opinion, it’s more gray than green, but I wasn’t the one who named it… ).

Aside from the previous main categories, there’s one more: Duanni/Tuanni (段泥/团泥). Originally it was called Tuanni (团泥/group or mixed clay), which referred to a mixture of different kinds of Zisha. Most people were illiterate at that time, and in the Yixing dialect the words Tuan(团) and Duan(段) sounded quite similar, so the two characters changed. Nowadays it’s called Duanni (段泥). It didn’t help that there was another character, also Duan(缎), that meant “Satin” as a color, which was a common color of the clay after firing.

Long Story short let’s get into a short overview of the main categories, shall we?

Zini — 紫泥 — Purple Clay

Zini (紫泥) is the most popular and the most common of all Zisha. It is the original clay which gave Yixing its fame, centuries ago. The “Yixing Purple Sand Mineral” (宜兴紫砂矿料), by Zhu Zewei (朱泽伟), also known as “The Zisha Standard”, distinguishes 21 kinds of Zini. The distinctions are based on their composition, location from which they were mined, and the depth they were mined from. Some notable variants that we’ll talk about are Dicaoqing (底槽清), Qinghuini (青灰泥) and Tianqingni (天青泥).

Zini(紫泥) from Huang Long Shan(黄龙山) Mine No. 2
Zini (紫泥) from Huang Long Shan (黄龙山) Mine No. 2

Zini 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 the low-quality tea the common people drank in those times.

The color of the finished Zini teapot is usually composed of various shades of brown and purple.

You can find out more about Zini: [HERE]

Hongni — 红泥 — Red Clay

Hongni (红泥) is a Zisha material named for the color of the clay after firing. It is a general category that can be divided into two subcategories, according to the raw materials used: Zisha Hongni (紫砂红泥) and Zhuni Hongni (朱泥红泥). We cover Zhuni later in this article, so when we talk about Hongni, we mean Zisha Hongni.

Benshan Hongni(本山红泥) from Huang Long Shan(黄龙山)
Benshan Hongni(本山红泥) from Huang Long Shan(黄龙山)

Hongni, in its raw form, has a reddish or yellow color with a relatively uniform texture. It’s quite dense but easy to break up. Unlike Zhuni, it is not water-soluble. Hongni has a similar performance to Zini during the forming and firing process. When made into a teapot, it has structural properties and general characteristics similar to Zini, but it is slightly less porous.

Some of the famous variants of Hongni are Dahongni (大红泥), aka The Legendary Dahongpao (大红袍), as well as Xiaohongni (小红泥), Hongpilong (红皮龙), and Jiangponi (降坡泥).

The color of the finished teapot is orange, or shades of red.

Zhuni — 朱泥 — Vermillion Clay

Zhuni (朱泥) is a special clay, because it is the only Zisha which is not originally from Huanglongshan (黄龙山), instead it is from Zhaozhuangshan (赵庄山).

During the Ming and Qing Dynasties the main source of Zhuni was Zhauzhuangshan and later Hongwei (红卫) Village Mine. There was really few Huanglongshan Zhuni teapots during this time, because Huanglongshan Zhuni comes from the deeper ore layers and therefore it was difficult to mine. However Huanglongshan Zhuni became more common during the 20th Century with the advancement of technology. The Zhuni at Huanglongshan has a smaller shrinkage ratio which allows it to be made into bigger teapots.

It is during the second half of the 20th Century when they found the most prized Zhuni among all, at Xiaomeiyao (小煤窑) or Little Coal Mine. The only bad thing about it, that it was extremely rare (only distributed in small 5-20cm patches among coal blocks and sandstone), and also really difficult to work with. Xiaomeiyao Zhuni has the largest shrinkage ratio and the lowest yield during firing (only 6 out of 10 teapots survive firing).

The original Zhaozhuang (赵庄) Zhuni (朱泥)
The original Zhaozhuang (赵庄) Zhuni (朱泥)

Zhuni is yellow in its raw form, and has a chalk-like texture. Unlike all other Zisha, Zhuni is water-soluble. Its shrinkage rate can be significant, and its plasticity is comparatively low. For these reasons, Zhuni is extremely difficult to work with, therefore in the past, only the greatest masters of Yixing were able to make pure Zhuni teapots, mostly they blended the clay with other Zisha, like Baini (白泥) or Duanni.

However, thanks to modern technologies like electric kilns, which allow precise temperature controls, making Zhuni teapots become easier, but it is still harder to work with than any other kinds of Zisha.

The finished Zhuni teapot has a very dense structure, and is therefore the least porous of all Zisha, almost like porcelain in nature. The color of the teapot after firing spans a range of reds: brownish, bright, orange and dark.

Lüni — 绿泥 — Green Clay

Lüni (绿泥) is the rarest of the common Zisha categories. Only around 2% of all Zisha is Lüni. It is named after the color of the raw ore. Like most Zisha, Lüni is from Huanglongshan (黄龙山); therefore, it is mostly referred to as Benshan Lüni(本山绿泥), aka Original Mountain Lüni.

Benshan Lüni(本山绿泥) from Huang Long Shan(黄龙山) Mine No. 4
Benshan Lüni(本山绿泥) from Huang Long Shan(黄龙山) Mine No. 4

Lüni needs to be high fired, otherwise, it can “spit black” (吐黑) or crack from usage. Lüni has the best air permeability and heat preservation of all Zisha. However, these properties can vary according to where the material was mined, and the depth from which it was mined.

After firing it usually has a kind of pastel yellow, satin, beige coloration.

Tuanni/Duanni — 团泥/段泥 — Group/Section Clay

Tuanni/Duanni (团泥/段泥) is not a single type of Zisha, but a mixture of the others. Usually, it is a mixture of Zini and Lüni, or Lüni and Hongni. Because of this, Duanni can be anything. It’s the most diverse and complex of Zisha, and can have the attributes of Zini, Lüni, Hongni in any proportion.

Benshan Duanni (本山段泥) from Huanglongshan (黄龙山) Mine No. 4
Benshan Duanni (本山段泥) from Huanglongshan (黄龙山) Mine No. 4

The color of the finished teapot can be anything in the range of and between the other Zisha types.

Some notable examples of Duanni include: Sesame Duanni (ZhimaDuanni/芝麻段泥), Gold Duanni (JinDuanni/金段泥), and my personal favorite, Crab Yellow Duanni (XiehuangDuanni/蟹黄段泥).


Well, I hope this was an informative overview of the basics of Yixing Zisha. In later posts, I’ll delve deeper into the various clays and techniques for making teapots. I also plan to make Q&A-s with some potters from Yixing.

Be sure to check back on this article later. I’ll keep it up to date so that it can be used as a reference for the western tea community.

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, like:
  • https://baike.taohuren.com/
  • http://www.yirenchupin.com/