USE OF PARTICLE SEARCH SOFTWARE FOR GROUNDMASS SPINEL EPMA STUDIES IN KIMBERLITE DRILL CORES AND ITS APPLICATION TO DIAMOND EXPLORATION

摘要

Electron probe microanalysis (EPMA) of indicator minerals is one of the cornerstones of diamond exploration. In most cases, these analyses are the first insight an exploration geologist obtains regarding the nature of a kimberlite. Such analyses give an indication into diamond potential as well as characterisation of the different facies. Standard procedure is to crush rock samples, separate the so-called indicator minerals and then embed them in epoxy for subsequent EPMA analysis. The disadvantage of this procedure is that some minerals, which may play a significant role in kimberlite interpretation, cannot be treated in this manner. The result is that these minerals must be analysed in situ in thin section slides. One such mineral is groundmass spinel.