Have you reviewed work from Gol-E-Gohar:

http://is.gd/yiqVhc
http://is.gd/WDaAZV

I know I'm being a bit pedantic for a Friday afternoon but we're talking about pyrite flotation here NOT pyrite reverse flotation. Its reverse flotation of magnetite where pyrite is floated.

Though the pyrite concentration looks to be lower (with S<0.5% in feed) it may be worth looking at the pyrite floats around the Kalgoorlie area in Western Australia as these systems are generally highly saline (off the top of my head KCGM Fimiston and Kanowna Belle) and do employ xanthates.

Good point! The little things do add up to the big understanding!
Let us know how your studies progress, and if there was useful material in the references we provided.

I would like to share this conference paper. http://is.gd/xaS9ki

Water quality is not a major issue in floating pyrite as demonstrated by numerous operations pH needs to be ideally controlled to the acid to neutral range and often copper sulphate is employed to improve flotation kinetics and recovery. The main issue is process water management. You will need a separate water circuit for the pyrite flotation circuit and not return the water recovered from this circuit to the head of the magnetite circuit if flotation separation is being practiced (would expect magnetic separation if it is magnetite). Why - because the residual reagents in the process water would cause the pyrite to float with the magnetite.