Recommend Stones

I was going to buy Yunzi biconvex stones, but I read something about them containing lead?

I don’t want to start a fight as I’ve seen happen on other forums lol. Are Yunzi ok? What are my alternatives?

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There was a pretty spirited discussion on Reddit about this topic. Officially, there is lead in Yunzi stones, but the level is minimal (~50 ppm for black, ~20 ppm for white), which clears them for sale in every country that regulates lead. On the other hand, there are anecdotal reports of higher levels.

In sum, I don’t think the lead is a concern. It’s not like paint, which lies on the exterior of the surface and can be scratched off. The lead is trapped in the lattice of the porcelain making up the stones. Unless you’re eating them or snorting them as powder, I very much doubt the lead presents a real health concern.

Editor’s note: I own Yunzi stones.


I am skeptical as to the actual dangers of miniscule amounts of lead in Yunzi stones, but I have read that there is no safe amount of lead.

I’m currently looking at glass stones, although I would love stones that are actually made from stone, or stone-like material.

It is sort of true that there has not been a determination yet if what a safe amount of lead would be. But that just means we don’t know the exact figure.

In reality, you will be exposed to lead to some degree throughout nearly every day. It is in the dirt, in car exhaust fumes, inside objects not marketed to children, etc.

Personally, I wouldn’t worry about Yunzi stones unless you have a habit of putting them in your mouth and sucking on them. Even the old Yunzi stones are probably fine for ordinary handling–I wouldn’t leave them around unattended children, though.

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