Abstract
A review of 785 pyrite analyses (Fleischer, 1955) indicates that 75 percent contain more than 10 ppm copper, 10 percent contain more than 1 percent copper, and the maximum concentration reported is about 6 percent copper. The conclusion was reached that “it seems probable that most, if not all, of (the copper) is present as admixed chalcopyrite or other copper minerals” (Ibid, p. 1005). A review of the literature indicates that this is a widely held view. Analyses by all standard techniques are suspect, unless it can be shown that the material is inclusion-free. However, electron microprobe analysis, having a resolution of one micron, is ideally suited to the study of minor elements and their distribution. Probe analysis has recently confirmed the presence of significant amounts of copper held in solid solution in pyrite (Frenzel and Ottemann, 1967). The present note further documents this fact.
