Abstract:Dickite is a relatively uncommon clay mineral, belonging to the kaolin group and having dioctahedxal structure. It occurs along the cracks and sli- ding planes at false roof and top of the coal bed (Permian Shanxi Formation) in Fengying mining area, Jiaozuo coal basin, and is 1-lOmm (generally 5mm) in thickness. It is usually white or greyish. white in colour, and grows grey when sub- jected to carbon contamination. The differential thermal analysis indicates that the endothermic valleys appear at temperatures h馆 her than 600t,that a comparatively intense exothermic peak occurs at 980℃,and that the mineral has considerably high degree of order. Absorption peaks are observed on the infrared spectrum curve from 3700 CM-1 to 3600 CM-1 with the character of gradual intensification. The six diffraction peaks at 20 values from 20 0 to 24 0 and the double peak at 2θ values from 35° to 40° on the x-diffraction pattern also denote the mineral of dickite. The electron microscope analysis demons- trates that this mineral assumes the shape of accumulated tower, and the che- mical analysis shows that its components axe mainly SiO2 and A1203 with some absorbed water-other constituents are rarely observed. This further con- firms that this mineral is undoubtedly dickite with pure chemical components. All these data will contribute to the genetic study of this mineral.