13.07.2015 Views

Feasibility Study and Technical Report - Pretivm

Feasibility Study and Technical Report - Pretivm

Feasibility Study and Technical Report - Pretivm

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Further gravity concentration test work was conducted on the blended rougher flotationconcentrate produced from the various flotation tests. The centrifugal gravity tailingswere subjected to cyanide leaching. As shown in Table 13.29, gravity concentration onthe reground concentrates recovered 37% of the gold from the GH2 concentrate <strong>and</strong>29% of the gold from the WZ1 concentrate. The gold leaching extractions from thegravity tailings were 84% for the GH2 sample <strong>and</strong> 75% for the WZ1 sample.Table 13.28Test Results - Gravity Concentration, Flotation, Secondary GravityConcentration <strong>and</strong> Cyanide Leach Combined Flowsheet (Flowsheet C) (2010 to2011)Primary Grind/Regrind SizesConcentrate Grade (g/t) Recovery/Extraction (%)Au Ag Au AgGF26/Composite GH2Primary Gravity Concentrate P80 125 µm 1,808 183 36.4 0.32Flotation Concentrate P80 125 µm 16 302 62.0 98.6Secondary Gravity Concentrate P80 7.1 µm 1,116 2,650 51.5 8.1Gravity Rougher Tailing - 5 189 31.3 76.9Gravity Panning Tailing - 70 927 17.2 15Intensive Leach on Gravity- - - 93.6 95.6Panning TailingLeach on Gravity Rougher Tailing - - - 61.3 64Head - 5 53 - -Overall Recovery - - - 90.4 71.2GF27/Composite SU98 *Primary Gravity Concentrate P80 123 µm 11,959 186 33.2 0.3Flotation Concentrate P80 123 µm 214 556 66.2 98.8Secondary Gravity Concentrate P80 6.9 µm 13,281 11,323 79.1 27.7Gravity Rougher Tailing - 35 264 19.6 61.0Gravity Pan Tailing - 69 1,412 1.4 11.3Intensive Leach on Gravity- - - 95.3 95.8Panning TailingLeach on Gravity Rougher Tailing - - - 97.2 66.9Head - 73 205 - -Overall Recovery - - - 99.1 78.9GF25/Composite WZ1Primary Gravity Concentrate P80 120 µm 1,151 194 26.4 0.4Flotation Concentrate P80 120 µm 12 163 70.6 97Secondary Gravity Concentrate P80 7 µm 646 1,600 50.4 9.1Gravity Rougher Tailing - 3 107 31.0 77.3Gravity Pan Tailing - 71 716 18.6 13.6Intensive Leach on Gravity- - - 94 96.5Panning TailingLeach on Gravity Rougher Tailing - - - 64.3 66.9Head - 2 25 - -Overall Recovery - - - 88.7 72.5Note:*Composite SU-98 is from the area between the West Zone <strong>and</strong> Galena Hill Zone.Pretium Resources Inc. 13-40 1291990200-REP-R0012-02<strong>Feasibility</strong> <strong>Study</strong> <strong>and</strong> <strong>Technical</strong> <strong>Report</strong> on the BrucejackProject, Stewart, BC

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!