Iron-pyrites come almost entirely from Department.
The table below gives the average production of zinc, argentiferous lead, iron-pyrites and other ores during the quinquennial period 1901f 905.
in some places sulphur is extracted from iron pyrites by one of two methods.
The conglomerate bands and quartzites contain large quantities of iron pyrites deposited subsequent to their formation, that in the conglomerates containing the gold.
The difficulty in separating zinc blende from iron pyrites is well known, and probably the most elaborate ore-dressing works ever built have been designed with this end in view.