Duanni (段泥) is the pale member of the Yixing family: the clay that fires beige, rice-yellow or gold instead of red or purple. It is also the clay where blending and colourants come up most often. This guide covers what independent sources agree on, and the open questions.
What duanni is
A co-occurring ore. Duanni is not a single mineral. It is described as an ore in which benshan green clay (luni) occurs together with purple clay, and sometimes red clay.
The name. Duanni is also called tuanni (团泥): in the Yixing dialect 团 and 段 sound the same, so the two names refer to the same clay. Sources offer different stories for where the name itself comes from.
Where it is mined. Mainly in the Huanglongshan area of Dingshu, Yixing — locally called 本山, "our own mountain".
How duanni fires
Grey in the ground, yellow in the kiln. Unfired duanni ore is light grey, greenish-grey or greyish-white. Fired in an oxidising atmosphere it turns beige or rice-yellow through to golden or yellow-brown; the exact shade depends on the ore mix and the kiln. At higher temperatures, or in a reducing atmosphere, it can turn greyish or blue-grey instead.
Why it is pale. Duanni and benshan luni are low in iron — about 1–4% iron oxide, less than red and purple clays — which is why they fire light.
Temperature and texture. Sources put duanni's firing temperature at roughly 1150–1200°C. It is described in the trade as coarse and sandy — "more bone than flesh" (骨多肉少) — a description rather than a measurement.
Benshan luni: the source clay
Benshan luni (本山绿泥) is a single ore from Huanglongshan that is green when mined, low in iron, and fires to a pale "pear-skin" or creamy yellow. It occurs as a thin seam only a few centimetres thick between purple clay and duanni layers — nicknamed the "dragon sinew" and described as "rock within rock, clay within clay" (岩中岩，泥中泥). It is rare and produced only in small quantities.
Golden Duanni and other names
Golden Duanni (黄金段) fires golden-yellow, and Chinese sources describe it as one of the better grades of duanni. Sources disagree on what it should look like (dark gold or bright yellow) and on where it comes from.
Aged duanni (老段泥) is described by some as clay stored for a long time that fires yellow with a reddish tint, by others as a darker duanni. Qing duanni has three incompatible descriptions in the sources we read. For Baiyu Duanni (白玉段) we found almost nothing reliable, beyond one description of white duanni as a high-firing clay that fires whitish.
Blending and colourants: the honest part
Natural duanni ore is described as scarce, and much duanni in use today is blended by hand — typically benshan luni plus purple clay. Some sources say this is normal practice and not a quality problem; others say most Golden Duanni on the market contains other clays or pigments.
Several sources report that titanium dioxide is added to yellow duanni to brighten it, and that TiO2 added to white clay is a common way to fake benshan luni. We can't tell you how common this is — only that it is a known concern worth asking a seller about.
In use
Duanni pots change visibly with use: they darken and gradually develop a sheen. Because the clay is light and absorbent, it picks up tea colour easily, and some sources warn that without prompt rinsing it can develop a blotchy patina. If a duanni pot turns dark once wet ("spitting black", 吐黑), sources blame under-firing, not the clay. Tea recommendations for duanni vary so widely — from green and floral teas to shou pu-erh — that we don't repeat them as advice.
Many duanni pots are wood-fired. In a wood kiln, ash lands on the unglazed pot and melts into a natural ash glaze, and flame paths leave fire marks; sources describe this changing colour and texture, but we found no source explaining why duanni in particular is so often wood-fired.
Duanni-family pots in our catalogue
We currently have 114 pots recorded under duanni-family names:
| Clay name (as recorded) | Pots in stock | Capacity range |
|---|---|---|
| Golden Duanni | 50 | 60–320 ml |
| Duanni | 27 | 50–240 ml |
| Aged Duanni | 15 | 85–260 ml |
| Baiyu Duanni | 13 | 80–180 ml |
| Benshan Luni | 4 | 100–180 ml |
| Qing Duanni | 2 | 130–175 ml |
| Qinghui Duanni | 1 | 110 ml |
| Songhua Duanni | 1 | 140 ml |
| Lipi Duanni | 1 | 100 ml |
See them all in our Duanni Clay Yixing Teapots collection.
A note on names: clay names in our catalogue are recorded as the maker or supplier gives them. We have not laboratory-tested the clays, and this guide does not certify any pot's ore.
Other clay guides: Zhuni, Zini, Duanni, Jiangponi. For an overview of all clay names, see Yixing clay types and colours; for shapes, start with the Xishi and Shipiao guides.