Warning, Yunzi Stones Are Dangerous To Health

[emerus]

The OP was a pretty serious allegation but wasn't it resolved? From a parent's perspective, I can see the lack of transparency and disclosure from YMI as troublesome. But the amounts of potential brain damage from licking a yunzi stone seem comparable to watching too much TV or heading a soccer ball.

They are as harmless as anything choking-size can be.

On a somewhat related note, I was told a great way to deter some pesky children from your Go table. My grandfather would tie some balloons around their game area so when my mom would lurk, he'd pop one and scare her off. It was probably a positive technique vs his opponents too. Balloon tesuji!

[Drew]

On a somewhat related note, I was told a great way to deter some pesky children from your Go table. My grandfather would tie some balloons around their game area so when my mom would lurk, he'd pop one and scare her off. It was probably a positive technique vs his opponents too. Balloon tesuji!

My child is cut from a different cloth. Pop one balloon and he'd run to find something sharp then return and "help" me pop the rest!

[moboy78]

What's more, I think it's also worth noting that breakfast cereals have iron and zinc in them, but people still eat them. So long as the potentially harmful substances are kept to a healthy level, there shouldn't be any issues.

This is stupid and dangerous advice. The body needs iron (e.g. for red blood cells) so some cereals are reinforced with it so we get enough. The body doesn't need lead, it has no known physiological use in the body and is poisonous, particularly for children.

My advice is to not ingest substances to point where they poison you. That is by no means stupid or dangerous. In my previous post in this thread there was not a single place where I said, implicitly or explicitly, that anyone under any circumstances should ingest lead. Admittedly, my example in your quote wasn't worded as well as it could have been nor was it the best example I could have used to prove my point; however, that does invalidate the rest of what I said nor does that make what I'm saying stupid.

[emerus]

What's more, I think it's also worth noting that breakfast cereals have iron and zinc in them, but people still eat them. So long as the potentially harmful substances are kept to a healthy level, there shouldn't be any issues.

This is stupid and dangerous advice. The body needs iron (e.g. for red blood cells) so some cereals are reinforced with it so we get enough. The body doesn't need lead, it has no known physiological use in the body and is poisonous, particularly for children.

My advice is to not ingest substances to point where they poison you. That is by no means stupid or dangerous. In my previous post in this thread there was not a single place where I said, implicitly or explicitly, that anyone under any circumstances should ingest lead. Admittedly, my example in your quote wasn't worded as well as it could have been nor was it the best example I could have used to prove my point; however, that does invalidate the rest of what I said nor does that make what I'm saying stupid.

Sorry, but your example was terrible and made your whole point seem stupid(valid or no). Iron and zinc are extremely helpful minerals and in no way comparable to lead which is simply poisonous to our bodies.

[tekesta]

I bought "Yunzi Stones" from Yellow Mountain Imports as a gift for my young children, so we can play baduk together. Later on after ordering, I saw online that this kind of stone can contain lead.

So when my order arrived I got a lead test kit from the local hardware store to check them for safety. It turns out that the stones sent to me did contain lead. This is unsafe for my children to use and maybe me too. It's not responsible for Yellow Mountain to be selling these stones to people. The page on their website doesn't say anything about lead even though I read that they already had this problem for many years http://chiyodad.blogspot.com/2008/01/le ... tones.html

Why do they keep selling them if they can't guarantee their safety for children? I think it's very unreasonable and possibly even illegal in the US.

I wanted to write my experience here to warn people that if you've also bought these stones from Yellow Mountain that they're not safe, especially for children. Also to advise people not to deal with this company because they're untrustworthy.

I'm very disappointed and unhappy with this experience and won't be doing business with Yellow Mountain again. Can anyone please recommend a better store where I can order some replacement stones that aren't polluted?

J Lee

Does this lead leach out (released into the surrounding environment), or is it bound within the substance of the Yunzi stone? This is an important consideration. As someone mentioned earlier in this thread, lead oxide is used in the Yunzi manufacturing process to make the glass-like material workable at lower temperatures; the worker pouring the molten stuff into the mold often has to work in close proximity to a super-hot furnace for long hours during the day.

If the lead is a real concern for you and you want to buy another product from another seller, one place where you can go is Gogameguru.com. They have a Cheap Go Set for about USD$10 and contains heavy plastic single-convex stones, all lead-free. (The board in this set is a foldable palstic mat, so if you prefer a solid board you will have to obtain it separately.). Also, you can go to http://www.yutopian.com/go and find plastic and glass stones.

As for Yellow Mountain Imports, it's a pity that they have eliminated several items from their Go-related inventory in recent years. I don't see single-convex marble stones anymore, nor the antibacterial plastic stones. It's a pity as well that they do not carry single-convex porcelain stones; Go-gamestore.com closed their doors back in 2011 or so and they used to sell these at a relatively low price, about USD$13 a set. IMO these are similar in look and feel to Yunzi, but at a lower price and (hopefully) without the lead.

[Carcosa]

I know Yellow Mountain Imports has lead free Yunzi stones now, and I wouldn't be surprised if they are all lead free now as I think they are all made in the same factory in China.

[nctu127]

Thank you for this information.

reddragon88