Benefits associated with two-stage spiral cleaning at McClure River preparation plant

The inclusion of the secondary spiral circuit in the McClure flowsheet has proven to be economically beneficial. It was shown to produce a pre-tax rate of return of 149% at a net realization of $25.00/ton. Additionally, after two years of operation, this secondary spiral circuit along with the balance of the spiral circuit has produced significant yield benefits associated with the froth flotation circuit and allowed the plant to increase its processing rate from 600 to 1100 tph.