Decomposition of rocks and ceramic materials with a small amount of sodium carbonate

A method for the decomposition of rocks and ceramic materials is presented in which only 2 parts of sodium carbonate are used for 1 part of sample. The fusion is made in a 75-ml platinum dish instead of a crucible. If silica is to be determined, the same dish is used for the fusion, the disintegration of the melt with hydrochloric acid, the evaporation to dryness, and the ignition of the silica.