Yixing safety?

[puerhking]

Sorry if this has been addressed already......
Is anyone else concerned about possible contaminants in their yixings? Given the porosity of the clay I would assume they would leach easily into tea. Could things like lead, nickel, cadmium etc. be in the clay itself or be introduced in process?

[olivierco]

Sorry if this has been addressed already......
Is anyone else concerned about possible contaminants in their yixings? Given the porosity of the clay I would assume they would leach easily into tea. Could things like lead, nickel, cadmium etc. be in the clay itself or be introduced in process?

In the clay normally not.
Introduced in process or mixed in the clay, there is always a possibility.

How to be sure? By buying from reputable vendors, you minimize the risks.
Or buy making some chemical analysis of tea brewed in your teapot.

[betta]

Lead tester is available worldwide, however for other heavy metals the testing method is still elaborate.
I would support olivierco's idea, to buy from reputable vendors. Otherwise, I'll buy old pots, hoping the largest portion of heavy metals leached out already

[MarshalN]

Honestly, I don't think "trusted" vendors know any more about the pots than you or I do.

[chamekke]

So now I'm very curious.

Has anyone here ever used a lead-testing kit on yixing wares?

If so, what did you find?

Has anyone ever analyzed their yixing wares for other heavy metals?

And - ditto.

[puerhking]

I agree with you MarshalN.......and perhaps the manufacturer doesn't even know. Obviously if it were a real problem people would be getting ill from it. It's just concerning when you combine that with pesticides and air born heavy metals from coal fired electric plants being put up every week. It would just be nice to know if there are toxins in the pots and how much is on the tea itself.

Man I am a real buzz kill.....lol.

[scruffmcgruff]

Has anyone here ever used a lead-testing kit on yixing wares?

If so, what did you find?

Back before I became apathetic about lead poisoning, I used a lead-testing kit on the zisha gaiwan (on the outside and on the glazed interior) from Dragon Tea House (on eBay), and it tested negative for lead.

[MarshalN]

I think I've asked this before, but... has anybody tried the lead test on a kuroraku ware piece?

Those are known to have lead. Now, if the lead test comes back negative on those... then you can just ditch them.

[chrl42]

Green colored yixing contains cobalt oxide, a black colored yixing contains maganese oxide, some red colored yixing contains iron red powder, however those are considered rather traditional methods since ROC period and heated about the same as normal yixing in a kiln. So they won't be melted into water, even if so they are not hazard chemicals to the body.

Problem is fake yixing teapots that have untrusted sources.
Yixing teapots require about 1200C (differs by a clay) to be heated, but so-called yixing wannabe clay-made teapots cannot bear at that temperature and be easily cracked. So temperature of heating is one consideration and other is they use industrial dyes from abandoned factories..

[Zodduska]

I think I've asked this before, but... has anybody tried the lead test on a kuroraku ware piece?

Those are known to have lead. Now, if the lead test comes back negative on those... then you can just ditch them.

I recently asked one Japanese pottery vendor about the presence of lead in glazes, here is his reply:

Though glaze containing a lead is used, those glaze has passed the test.
Since the pottery currently sold at Japan is taking the test which investigates leaden content in an industrial examination site, it is uninfluential on a human body.
The glaze currently used for the works which I sell has passed the test.
And most glaze which contained the lead recently is not used in Japan.

[betta]

Honestly, I don't think "trusted" vendors know any more about the pots than you or I do.

I remember stephane of teamasters has conducted lead test with all of his teawares. I'd consider him to be one of the trusted vendors.

The clay itself comprises also minerals = metals, etc in a microstructure cage and it shouldn't leach out. The heavy metals which dissolve in water are those not present originally in the clay (free metals). Some people are using explosives to blow up the yixing rock mountain and the explosives along with those detonator contain heavy metals and get grounded along with the clay.
After intensive repetitive 10-20 years of pot use, its concentration should get low, but still harmful to human body, especially if you already use it for 20 years
Chemically you can do tests with the brewed water using specific reagent for each heavy metal. It's way too elaborate and unaccesible for those who don't work in chemistry lab.

[hop_goblin]

Lead tester is available worldwide, however for other heavy metals the testing method is still elaborate.
I would support olivierco's idea, to buy from reputable vendors. Otherwise, I'll buy old pots, hoping the largest portion of heavy metals leached out already

I am with Bett. If this is a concern just buy older pots. However, if you still are wanting to buy a new pot, then I would recommend buying pots with a maker's certificate. You know, you have seen these on the net, they are generally potters holding their work. I believe most show their creditials and gov't certification. BUT when you are dealing with China, there is no way to know if even these are authentic.

[BonBon]

So as far as reputable dealers would go, would anyone consider Yunnan Sourcing reputable? Or should one be careful considering their low price tags?

[britt]

I completely trust Guang at Hou De and I consider him to be honest and very well informed about tea and teaware. I buy only used/older Yixings because that's all he sells. I've purchased 12 from him. The only new pots I've seen him carry are from Taiwan. I find those to be very good as well.

I have recently purchased 2 Yixings from Jing Tea Shop in China. I was very hesitant to buy anything directly from China, but I have been very happy with those two purchases as well as some Yixing and Jing De Zhen cups I also bought from them.

As has been mentioned, dyes and chemicals have been found in quite a few Yixings, and not just cheap ones. Genuine clay from Yixing is claimed to be lead-free. It is questionable whether the real cheap pots even use real Yixing clay.

I had a problem with one of the first two Yixings I purchased. They came from the same vendor and tea didn't taste very good from either. In one, it tasted very bad. These pots were claimed to be genuine Yixings and the price ranged from $35 to $50. When I contacted the vendor, who does have a good reputation, they very honestly stated that their Yixings are purchased in open markets similar to flea markets. To me, that means they probably don't really know what they're buying or reselling to us here in the states. Their intentions may be good, but I ditched those two pots and started buying used ones from Hou De. Good intentions with limited experience and knowledge can still be dangerous.

There is another option; there is a Taiwanese clay pot sold at The Fragrant Leaf and Rishi that is very good but is also inexpensive. It is only $25, which is a small price to pay for safety. I have owned this pot and had good luck with it. I gave it away only after I purchased quite a few real, and much more expensive, Yixings.

[betta]

I had a problem with one of the first two Yixings I purchased. They came from the same vendor and tea didn't taste very good from either. In one, it tasted very bad. These pots were claimed to be genuine Yixings and the price ranged from $35 to $50. When I contacted the vendor, who does have a good reputation, they very honestly stated that their Yixings are purchased in open markets similar to flea markets. To me, that means they probably don't really know what they're buying or reselling to us here in the states. Their intentions may be good, but I ditched those two pots and started buying used ones from Hou De. Good intentions with limited experience and knowledge can still be dangerous.

Britt, not to discredit the vendor, but could you share me via PM the vendor you mentioned about?