My teochew I bought for $4 in 75. I still have a couple of extra.
This is an Internet picture so I assume this form hasn't changed much.
I used it in a corporate envirnoment for 20 years. I could rap the
infuser on a napkin to dump the leaves and it never cracked. It was
impervious to a microwave nuclear meltdown. The clay is hard and
smooth which oddly resisted patina buildup. The interior surface just
got dark but never something that would rub off with a finger. I used
two sizes. I used the smaller 250ml for work and the larger 500ml for
home. I haven't seen any since.

http://i10.tinypic.com/2ue1he0.jpg

Jim

wrote:
> Thanks for adding your insight Jing.
>
> You are right about the Chao Zhou teapots. Interestingly, they don't
> make heavy roasted oolongs overly bitter, even though the clay is not
> porous. I have a small collection for historical and cultural value,
> but I prefer zisha teapots. Chao Zhou teapots just don't have the same
> capacity to improve texture and flavor as zisha.