Wellgreen Project Preliminary Economic Assessment ... - OTCIQ.com

Prophecy Platinum Corporation – Wellgreen Property – Project 50149-001
1.7%-2%, respectively. Thus, the rougher flotation upgrading index for copper is between 4.5
and 5.5 and that of nickel is between 4 and 4.8, this is a reflection of the high mass pull used.
• The distribution of pyrrhotite, which is the main iron sulphide mineral in the ore, appears to have a
close correlation with nickel recovery. The pyrrhotite content of the bulk concentrate reached a
maximum level at 18.8%. Contrary to both copper and nickel, pyrrhotite grade continuously
increased as the flotation time increased.
• The pulp pH was at a natural level of about 9 in the primary flotation tests. This pH is not high
enough to depress pyrrhotite. Pentlandite flotation is also expected not to be negatively affected
at this pH. Sodium Isopropyl Xanthate was used as the main collector and it was stage added to
the flotation cell with the total addition of 70 g/t. Details are shown in Appendix E.
• Pt and Pd recoveries were slightly higher at coarser primary grind size of 144 microns.
• While Cu and Ni kinetics were seen to be quicker in the test F6, the final recoveries were
ultimately the same.
4.1.1.2. Effect of Pulp Chemistry
In addition to SIPX, collector PAX was tested. PAX is particularly effective for a stronger collector and it is
non-selective collector which also renders Mg minerals to float. SIPX has the potential to improve the
selectivity of nickel sulphide flotation therefore increase the nickel recovery.
The effects of this collector on copper, nickel, and PGM recoveries are shown in Figure 19.
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