From what I gathered this my understanding of the black pots:Bok wrote: ↑Sun Jul 18, 2021 8:03 pmAnother thing on my mind recently is what I used to distinguish as “Wuni” and “Whuhuini” in the past. These two differently used terms had been given to me by more experienced collectors and Yixing experts.
Whuhuini explained as ash covered reduction firing, Wuni as a considerably less defined “also-dark-grey-reduction-fired-but-different” category. I did not question this at the time, but in hindsight it does not make any sense.
_For one: why would they go through the trouble to cover some in ash and others not?
_It does not sound like something Yixing potters would do, randomness and imperfection were not sought after. They took great care as to that pieces did not have random firing effects happen.
_there are seemingly no written sources on either one of those methods, as far as I am aware.
From my observations and from handling dozens of these grey pieces I have come to the conclusion that it is much simpler than that: Reduction fired, full stop.
The difference in colour simply explained by the different underlying clay at the base. Duanni for example usually results in a yellowish grey that sometimes can appear dark olive green or brownish grey. Other clays like Zisha ends up more dark blueish grey.
Further evidenced by the fact that the supposedly Zisha reduction still shows the silvery mica spots, while the green ones do not.
All this to say, apologies if I furthered this confusing and possibly not correct terminology of Wuni and Wuhuini by referencing it in the past. Personally I will only be using reduction fired from now on.
All black / grey pots are reduction fired or dosed with manganese oxide in later F1.
Wuni is an actual ore, which is black, dark gray, hence the name 乌泥.
Wuhui 捂灰 or wuhuini 捂灰泥. Is a reduction fired teapot, using the ancient ash firing technique. Which was a uniquely developed technique to reduction fire teapots in an oxidative kiln environment. It was initially / usually done to cover firing previous firing flaws, like efflorescence or fire marks.
Then there was also "real" Heini. Which is reduction firing in the modern sense, as the kiln it self was in a reduction state. It either happend accidentally or intentionally. These are more black, dark than the Ash fired counterparts, not so much grey. Those pots are extremely rare, due to the knowledge not being available. They are usually high iron zini / hongni teapots. Nothing "magical" or legendary clay.
Then an exemption, but often confused with the previous three is Qinghuini. Which is a special kind of grey brown zini. If I remember correctly those have naturally higher manganese content which gives them the greyish tone in oxidative firing.