Data Set of Major Element of Red Sandstone Tafoni Samples in Danxiashan

The major element analysis of 3 tafoni interior surface powder samples and 1 original sandstone powder sample was conducted on Agilent 720 inductively coupled plasma emission spectrometer (ICP-OES). During the experiment, about 0.05g of powder sample was placed in a PTFE container, and 0.6 ml HF and 3 ml HNO3 were added. Then the sealed container was placed in an electric furnace and heated to 185 ° C for about 36h. After cooling, heat the container on the hot plate and allow it to evaporate to dryness, then add 200 ng Rh as the internal standard, then add 2 ml HNO3 and 4 ml water. Seal the container again and place it in an electric furnace at 135 ° C for about 5h to dissolve the residue. After cooling, it is measured by ICP-OES with dilution factor of 1000. The sample was digested by alkali fusion method to determine the content of silicon dioxide. Dissolve 0.05 g of sample in a silver crucible with 0.25 g NaOH at 700 ° C for about 30 min. After cooling, dissolve with hot water and acidify with 5 ml HCl, and finally add water to 250 ml for ICP-OES measurement. About 1g sample is used for LOI. The sample is weighed in a porcelain crucible and heated in a muffle furnace at 900 ℃ for about 1 hour. The weight difference before and after ignition is LOI.