Petuntse (from 白墩子 in pinyin: bái dūn zì), also spelled petunse and bai dunzi, baidunzi, is a historic term for a wide range of micaceous or feldspathic rocks. However, all will have been subject to geological decomposition processes that result in a material which, after processing, is suitable as an ingredient in some ceramic formulations. The name means "little white bricks", referring to the form in which it was transported to the potteries (compare ball clay).