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

Prophecy Platinum Corporation – Wellgreen Property – Project 50149-001
In order to quantify the degree of liberation of Cu and Ni minerals and describe mineral textures and
associations, the bulk cleaner concentrate and the final products of locked cycle test were also submitted
for QEMSCAN analysis. The QEMSCAN results supports split type of flowsheet in which primary
roughing is to focus on recovery of the reasonably liberated material.
Following the preliminary testing, split flowsheet optimization testwork to optimize the flowsheet through a
more detailed program was started. The proposed split flowsheet recommends taking advantage of the
parallel cleaner lines presently used in the commercial operations. The strategy would be to direct a
rougher concentrate, rich in copper and nickel minerals to one of the lines and to direct a scavenger
concentrate, rich in pyrrhotite to the other line. The advantages of decoupling the cleaners would be that
collector and CMC conditions could be customized to the floatability of each mineral class. Specifically,
the copper and nickel minerals are known to be responsive to very low collector conditions. This low
amount of collector is anticipated to result in significant improvements to the flotation separation of copper
from nickel. On the other hand, the pyrrhotite is known to require high amounts of collector to recover
acceptable levels of sulphides. It is predicted that the proposed flowsheet will result in the production of
better quality copper concentrates and better process control in the commercial operation.
The viability of the split flowsheet was confirmed by means of locked cycle testing through re-circulation of
middling streams. The results indicate production of a bulk concentrate with 12% Cu+Ni grade at the
average Cu and Ni recoveries of 88% and 67%, respectively. At the same test conditions the combined
Pt, Pd and Au grade of 10.5 g/t at 46%, 73% and 59% recoveries, respectively would be expected.
In summary, within the limits imposed by its mineralogy, the ore sample responded very well to the split
flowsheet with a basic reagent regime. The Fe/MgO ratio and MgO content of the final concentrate were
within the accepted limits in this circuit.
The testwork completed thus far on the High Ni Composite show the production of a bulk concentrate with
14.5% Cu+Ni grade at the average Cu and Ni recoveries of 88% and 73%, respectively. At the same test
conditions the combined Pt, Pd and Au grade of 9 g/t at 38%, 73% and 62% recoveries respectively, was
produced.
Based on the results and observations of this test program, a number of recommendations are made for
future testing. These additional tests would help to increase the confidence in the metallurgical
predictions and to further the development of this material.
• It is anticipated that improved performance is possible in terms of Ni and PGE grade and recoveries
through better combinations of reagent selection and optimization.
• Variability testing extended to:
o Production composites, lithology composites, special location and grade variance. Point
samples should be used to confirm the developed flowsheet from a geometallurgical
perspective.
SGS Minerals Services
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