The clay used to make Zisha pottery is characterized by its sandy yet sticky texture, combining flexibility with strength, excellent plasticity, and a rich variety of colors. Common types of clay include:
- Purple clay (actually deep ochre or brown),
- Cream-colored white clay,
- Orange-yellow clay,
- Vermilion red clay (Zhuni),
- Dark green clay,
collectively referred to as the “Five-Colored Earth” (though in reality, they are diverse mineral ores).
The clay is crushed, kneaded, and shaped into pottery. After firing in the kiln, the surface becomes smooth and lustrous, with fine granular textures, showcasing the rustic yet refined quality unique to sandy clay. Since purple clay is the most commonly used, the pottery is generally called Zisha (Purple Sand) ware.
Primary Raw Materials for Zisha Pottery
The clay used in Zisha pottery is collectively called Zisha clay, but it actually consists of several types, mainly:
- Zini (Purple Clay, historically called “Qingni”)
- Benshan Lüni (Green Clay, also known as Tuanshanni)
- Hongni (Red Clay, also called Zhuni)
- Shihuang (Ochre Clay)
1. Zini (Purple Clay)
The most commonly used material in Zisha pottery, Zini is found within Jiani (a hard clay rock, also called “armor clay”), a type of sandy siltstone. When unweathered, it is called Shigu (stone bone) due to its hard, block-like structure resembling “iron armor,” hence the name Jiani (armor clay). Since Zini is embedded within Jiani, it is also called “rock within rock” or “clay within clay.”
Other variations of Zini include:
- Lipi Ni (Pear-Skin Clay): Fires to a frozen pear color.
- Danhong Ni (Light Red Clay): Fires to a pine-flower yellow.
- Danhuang Ni (Light Yellow Clay): Fires to a jade green.
- Mikou Ni (Honey-Mouth Clay): Fires to a light ochre.
2. Benshan Lüni (Green Clay)
Also found within Jiani, Benshan Lüni is another major type of Zisha clay. Its raw ore is eggshell blue with a smooth, greasy texture. More precisely, it is sandwiched between yellow slate and Jiani, earning it the name “Jianzhi (interlayered fat).” It shares the same mineral layer as Zini but acts as a transitional layer between Jiani and Zini. After firing, it turns a pale yellow.
3. Hongni (Red Clay)
Another essential material for Zisha pottery, Hongni ore is orange-yellow and located at the bottom of clay deposits, hard as stone—hence also called “Shihuangni (ochre clay).”
Hongni is scarce, and its color varies. High-quality, uniformly colored Hongni must be mined and stored separately to ensure purity. After firing, depending on iron content, it can appear in shades of cinnabar red, vermilion purple, or crabapple red. Due to its rarity, it was historically used for small teapots exported to Southeast Asia (“Shuiping” pots). Nowadays, it is mostly used as a slip clay to produce red-glazed teapots or pots.
Other Rare Clays
Additional types include:
- Lüni (Duan Clay)
- Dahongni (Bright Red Clay)
- Wuni (Black Clay)
- Baini (White Clay)
- Molüni (Dark Green Clay)
These clays are deeply embedded in rock layers, mixed within Jiani, and can also be used to make Zisha teapots. However, they are extremely rare, softer in texture, and have lower heat resistance than Zini, requiring separate firing or use as additives.
