Zhuni is very yellow ore, more yellow, better Hongni. On Zhuni, is special clay cause it has different characteritics than other clay. Unlike other clay(Huang Long mountain), birth place of Zhuni is Zhao Zhuang mountain, which is Lao Zhuni. Zhao Zhuang Zhuni, actually is what you can find from museum. Most of Zhuni today is from Xiao Mei Yao (near Huang Long mt.) and Hu Fu (aka modern Zhuni). Each Yixing clay has a different ideal temperature of firing, different temp has to do with crystallization. Crystallization is important cos it will lead the clay no smell, no blot, better patina and better functioning. Normal temp for Zhuni is less than 1100C, Zhuni is of very small particle so sees crystallization at lower temp. Zhuni is a clay that shows highest rate of shrinkage. Normally over 20% and Zhuni is of mud-like clay. That makes working on Zhuni different, should make it quick with less touching.