Study on Microstructure of Nano-minerals in Chrysanthemum Stone

Chrysanthemum stone is a diagenetic celestite nodule widely distributed in the Permian Chihsia Formation of South China. The microstructure of chrysanthemum stone from Liuyang was studied using scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray energy dispersive spectrometer (EDS). It was found that the petals in chrysanthemum stone from Liuyang retained the original celestite and their rectangular pyramid shape, but silicification was observed in celestite petals. In chrysanthemum stone, there are many types of nanometer minerals, such as amorphous silica nanometer threads, CaCO3 or SrSO4 nanometer grains, CaCO3 nanometer bands and lamellas. Some amorphous silica nanometer threads were enclosed by nano-crystals, which were related to magnesium.