Zisha means "purple sand", and it is the loose name for all clay from Yixing. Within it are three families: zini, the purple clays; hongni, the red clays, of which zhuni is the densest and brightest; and duanni, the yellow, cream and grey-green clays. Each comes from a different ore, fires to a different colour and behaves differently with tea. For most teas, zini is the safe choice.
What does zisha actually mean?
Zisha is used two ways. Loosely, it means any clay from Yixing. Strictly, it means the purple clay, zini, which is what most Yixing pots are made from. When a seller says "zisha", ask which they mean.
All three families start as rock, not as soft clay dug from a riverbank. The ore sits in thin seams deep underground, much of it mined 40 to 75 metres below the surface. Once mined, it is left in the open for years until it weathers and breaks into pebbles about the size of soybeans. It is then ground, sifted, mixed with water, pounded into blocks and stored in sealed, damp cellars. A year of cellaring is the minimum. Most potters believe older clay is easier to work and makes better pots.
That origin shows up in the finished pot. Under a magnifier, Yixing clay has many visible grains, because it was crushed rock. Coarser sifting leaves more sand and a more textured, open body. Finer sifting gives a smoother surface. Yixing ore is also high in iron, often around 8 to 10%, which is a large part of why it fires to such deep colours without a glaze.
What is zini?
Zini is purple clay, the main Yixing family and the one most pots are made from. It fires anywhere from light reddish brown to deep purple-brown, depending on the ore and the kiln. It is the most forgiving clay for tea: it holds heat steadily, breathes well and gives a smooth, bright liquor with almost anything.
Zini ore often lies beneath layers of duanni ore and muddy clay, which is why it is sometimes described as the clay hidden inside the clay. Different seams have different characters. Di cao qing, from a lower stratum, is one of the more famous names.
Zini was the original teapot clay. Ming dynasty teapots were large, and only zini could be fired at that size without slumping, so for a long time it was the only clay mined for pots. All the modern pots in our range graded Bronze to Diamond are zini. The grade describes the quality of the clay within the family, not a different colour. For how the grades differ, read Yixing clay grades explained. For a zini pot at the top of the scale, see the Ju Lun Zhu 120ml in Diamond grade.
What is hongni, and how is zhuni different?
Hongni means red clay. It is higher in iron than zini, fires at lower temperatures and warps if the pot is too big, so red clay is used mostly for small pots. Zhuni, "vermilion clay", is the densest and brightest of the reds. It shrinks so much in the kiln that many zhuni pots crack during firing.
That shrinkage is why zhuni pots are usually small and thin-walled, and why old ones are expensive. Every surviving pot carries the cost of the ones that broke. The ore comes from the bottom of the seams and is as hard as stone. Its old name, shi huang, means "stone yellow". Firing turns it vermilion.
Red clay has a long export history. Small hongni pots went to Europe in the late seventeenth century, and the small gongfu pots sold into southern Fujian and Southeast Asia in the same period were mostly red clay. From the 1950s, a softer yellowish ore found near Chuanbu and Fudong in Yixing came into use. It fires red and behaves like the old red clay, and it is often called "little hongni".
Red clay is dense and rings high when tapped. It holds heat close and keeps aroma lively, which suits fragrant, lightly oxidised oolongs, dancong and yancha. It breathes less than zini, so it is less forgiving with dark, aged teas. The Hong Pi Long Xiao Ying Hu 195ml in our range is made from Zhao Zhuang hong ni, a red clay named for the village it comes from.
Be careful with red pots on the open market. Iron oxide turns ordinary clay red, and much cheap "zhuni" is exactly that.
What is duanni?
Duanni means "segmented clay". It is the yellow, cream and grey-green family, named because its ore is found in sections between seams of purple ore. It fires anywhere from creamy white to greyish yellow, and it is the most open and breathable of the three families.
Some duanni ores are green when mined and turn cream after firing. "Sesame duanni" shows dark grains like sesame seeds through a pale body. Because the ore comes in short sections, supply has always been small, and much of it went into small pieces or decoration on zini pots.
A duanni pot suits green, white and yellow teas, where you want a lighter hand and less heat. As with red clay, colour is easy to fake: copper oxide is used to make imitation duanni from other clay.
What about green, black and blue Yixing clay?
Treat them with suspicion. Yixing clay was once sorted into five colours: purple, red, yellow, green and black. Natural green and black ores are now close to non-existent, and blue never occurred naturally in Yixing ore at all.
Most coloured pots today are coloured with metal oxides: cobalt for blue, chrome for bright green, manganese for black, iron for red and copper for yellow. The practice dates back to the Republic era (1911 to 1949). The legal limit for these additives is reported as 0.5%, which no buyer can check. Some black pots are coloured by the firing instead, by smothering them in ash in the kiln. A bright green or jet black pot is the clearest warning sign in the market. Our guide on how to tell if a Yixing teapot is real or fake covers the other signs.
What do "qing shui ni" and "raw ore" mean on a listing?
Both are claims about purity. Qing shui ni means clay made from a single ore, unblended. "Raw ore" (yuan kuang in Chinese) is used by sellers to mean clay made from ore with nothing added. Neither can be checked from a photo.
Blending, called pin pei, was once a real craft. Old masters mixed ores for colour and for the way a blend handled a particular tea. Much of that knowledge was never written down and is now lost. For that reason, many people who test pots against each other now prefer a clean single-ore clay to a modern blend. Our Biandeng 125ml is listed as raw ore zisha in that sense.
Which clay suits which tea?
Zini for most teas, red clay for fragrant oolongs, duanni for green, white and yellow teas. These are tendencies, not rules. The quality of the ore and the firing matter more than the colour.
- Zini: puerh, liu bao, cliff tea, most oolongs. The all-rounder, and the right first pot.
- Hongni and zhuni: dancong, high mountain and other aromatic, lightly oxidised oolongs. Also yancha, if you want to lift the fragrance.
- Duanni: green, white and yellow teas.
Shape matters too. For which shapes suit which teas, read which Yixing teapot shape for which tea.
If you only buy one pot, buy zini.