Pyrrhotite, Fe1xS, occurs frequently in nature and is commonly
considered as gangue in the production of industrial minerals commodities.
This is the case for high purity calcium carbonate (CaCO3)
deposits used in the production of micronized ground calcium carbonate
(GCC) for the paper industry. It has been shown by Bunkholt
and Kleiv (2013, 2014), that the presence of even very small concentrations
of pyrrhotite (97%, it is of great