Tead Off wrote:I don't know anyone who has had their Yixing pots tested. I've also never heard any 'hearsay' about Yixing clay being contaminated, but wouldn't be surprised if there was, as China has about as bad a reputation for pollutants and contaminants as any country could have. Leaking would definitely be the prime vehicle for contamination of the mines. But, I would think that the gov't and business community surrounding the pottery industry in China would have done some testing by now, as Yixing is no small matter to the Chinese as well as some of the richest people in the world.
I think we are jumping to the conclusions too fast. One of the reasons why I decided to go ahead and test my pots is because I am tired of reading exchanges on TC discussing whether Yixing pots are contaminated or not.
I would like to emphasize that my study was done on a rather small sample (5 teapots, obtained from relatively reliable vendors). I did not test any red clayware, of which there are concerns it may be mixed with (possibly) contaminated oxides. In fact, that is my next task, as soon as I save up some money for it. So, we cannot extract many conclusions about the Yixing industry from this study.
In addition, as I already pointed above (and so did John) there are environmental reasons to believe that Yixing and Jiangsu are extremely polluted places. If somebody is still skeptical and is holding strongly to the rather romantic image of Yixing, he or she should take a look at this map of the so-called "Cancer villages" in China:
https://www.google.com/maps/d/viewer?ms ... GsxnMyxV3c
and notice the astonishing concentration of them located in Jiangsu province, not far from Yixing.
Let me also point out that I am not the first to test Yixing pots in Taiwan. One of my most trusted vendors, Mr. Su from Taichung, has been doing it for a while. In fact, I am following the idea of sending my pots to SGS taking his practice as example. Please, see:
http://www.puwangtea.com/%E6%82%A8%E6%9 ... 80%BB.html
Use Google translation if you cannot read Mandarin, to get a rough idea of what is going on. Mr. Su is not only a tea vendor, but also teaches about Tea Culture and Yixing Pottery at National Chung Hsing University in Taichung. He has been to China many times, has bought ores there himself, and has commissioned the making of teapots that he sells in his shop. The pots are expensive and a bit on the large size for my taste, although I own a few of them. He always tests four samples for each type of ore (modern zhuni, duanni, zisha) out of the contamination concerns. But of course, he would not sell or tell you about anything that has tested positive (probably not, because he controls the entire process, something that we, as customers, cannot afford).
At the bottom of the same web page, you will find the links to the videos of the documentaries made by CCTV, which uncovered the scandal.
Therefore, that there is contaminated Yixing clay around, I think it is undeniable (wert also pointed to me in private communication that
some lead tainted had been used in the making of slow cookers in 2008 by
a famous brand. Maybe he can provide more details about that scandal).
Whether the problematic clay has made it into the "good teapots" that Tead Off was referring to above, I have no idea. But, to quote Donald Rumsfeld:
" There are known unknowns [...] But there are also unknown unknowns. There are things we don't know we don't know
" about the Yixing Industry
Therefore, instead of continuing discussing 'unknowns', let's take a pragmatic (experimental) approach and test and measure. And discuss with real data on the table, instead of just assumptions.