The versatility of the PIXE method with microbeams of protons as a non-destructive, in-situ probe for trace element analysis in the geosciences has been demonstrated in an ever increasing number of cases. While in most applications the method can be considered as derivative or as an extension of electron microprobe methodology, features unique to the proton microprobe enable new approaches to hitherto intractable problems of analysis. An appropriate niche has been established in igneous mineralogy and petrology, with important implications both in the basic geosciences as well as mineral industry applications, particularly in the diamond exploration industry. This paper reviews recent advances and discusses the advantages and limitations of current micro-PIXE applications in the geosciences in view of other competing and complimentary methods
