Classification of chromatographic methods Chromatography is the name given to a particular family of separation techniques of great effectiveness. The original method was described in 1903 by Tswett, who used it for the separation of coloured substances, and the name chromatog raphy stems from this. However, the limitation to coloured compounds never really obtained, and most chromatographic separations are nowadays performed on mixtures of colourless substances, including gases. Like fractional distillation, chromatography relies on the relative movement of two phases, but in chromatography...