This investigation was concerned with two aspects of the colour-zoning in tourmaline: firstly, the origin of the green and pink colours ; secondly, the reason for the apparent incompatibility of these two forms. Much of the previous work on the colour of tourmaline has involved the use of emission spectra. This method provides information as to which elements are present; it does not, of course, indicate which of the twenty or so elements identified is responsible for the colour, although it may be possible to infer this. Absorption spectra, on the other hand, are directly concerned with colour. They have been employed quite extensively in Germany, and more recently in Russia, but the earlier data and instruments were often inadequate. The last decade has seen marked improvements in the technique of absorption spectroscopy, particularly in the development of photo-electric methods for the quantitative recording of spectra, and the method is likely to prove one of increasing value.