In more than 25 years of handling Yixing teapots, I have only seen one teapot of mine crack. It was my thinnest one. I didn't even hear it crack. I noticed a very faint hairline becoming worse and now it leaks slightly if I brew tea in it, which I still do sometimes. It's an 80's pot and could be a zhuni.
Still, I never think twice about pouring boiling water in or over my pots. They should be able to handle it if they are made well. Being high fired doesn't mean they are susceptible to cracking. Porcelain are high fired and I've never had any porcelain crack on me. For me, thinness would be a sign of possible weakness in a pot. Most Yixing ware are battle hardened soldiers ready to face duty at a moment's notice. But, then again, nothing lasts forever.
Re: Gentle preheating: Are older Yixing pots more fragile?
JRS22 wrote:Every time you use the pot, or just the first time?Alex wrote:What I do now with high fired clay is to half fill with room temperature water and then pour in boiling. This seems to work great.
Everytime but that's only as I've had a pot crack. As Tead said you shouldn't have to. My Zhuni pot is well loved prior to me owning it. I bet the last person didn't pre heat. And the clay seems far better then my last modern zhuni