The fluorites of the Transvaal occur in different rock-types, viz in the dolomite of the Transvaal System, in acidic rocks (red granite and granophyre of the Bushveld igneous complex and Rooiberg felsites), and in alkalic rocks. The purpose of this study was to determine:
(1) What minor elements are present in selected fluorites.
(2) What the effect of these elements is on the respective cube-edges.
(3) Whether these elements have any geological significance.
Fluorite displays a wide range of colour; both colourless and distinctly coloured specimens were examined. Differently coloured varieties could in some instances be taken from the same sample. The choice of coloured varieties in the different rock-types was nevertheless limited. Only light-coloured fluorites occur in the dolomite, whereas the alkalic rocks yielded only very dark purple specimens.