tingjunkie wrote: ↑Thu Jun 14, 2018 5:40 amPersonally, I don't subscribe to a rule about older clay always being better, but there are some considerations people have not mentioned yet. I may have my time periods or years off, so please correct me if I'm mistaken:
1) Clay Processing: Prior to ROC period most clay was crushed and processed by hand. The Yixing ores were crushed by hand, or in a grinding mill powered by livestock. This contributed to a certain level of clay particle size and porosity. After ROC, it was more common for the ore to be crushed by machine, and lead to a different level of porosity. I also believe that once clay blocks were made from the ore, in the past they were aged for longer than in Factory times. Generally speaking, the longer a clay is aged or "fermented" the better for the teapot. The Factories were trying to crank out lots of Yixing wares, and aging the clay for decades was not in their plan. Finally, when clay is worked entirely by hand, and teapots are entirely hand built by beating slabs of clay in to shape, you're going to end up with a different porosity level than when pots are half hand made or completely mold made. People talk about how beating the clay by hand creates a smooth outer "skin" to the clay, and achieves a double layer, each with its own porosity.
2) Firing: Prior to the 1960's, wood-fired dragon kilns were the typical way to fire Yixing pots. After 1960's the Factories switched to using coal and gas powered down-draft and tunnel kilns instead. Later on past F1 days, even electric kilns were used more frequently, changing the characteristics of the teapots yet again. Of course these very different kilns will have different effects on how the teapots come out and perform.
3) Clay Masters: Back in the old days, Yixing had master potters, master calligraphers, AND clay masters. The latter were folks who only processed clay, and were often not potters themselves. I get the impression that a lot of their specialized knowledge has been lost over the years.
I'm not trying to imply fully hand made pots will always outperform half-hand made pots, or that dragon kiln pots are always superior to downdraft kiln pots, but there's definitely something to be said for Yixing's magical reputation being formed well before the advent of the modern processes invented in the later half of the 20th Century. I think there's also something to be said for people who are passionate about anything to romanticize the past and declare that things just aren't like they used to be, whether that's true or not.
+1. I agree with tingjunkie and steanze on their inputs. Back in the early days i.e. ROC, uniformity is extremely rare as evert pot is handcrafted and clays are also processed by hands. You will also tend to find more impurities in early period pots as compared to the modern filtration methods used in our time and age.
To add to the already excellent inputs... craft masters / artists who can afford it will also tend to buy and store their own clay. These clays are sometimes left to age over time. This aging factor of the clay also plays a part in the overall character of the clay over time.
my 2cents....
Cheers!!