Copper-Molybdenum (Gold, Silver)
|Ownership:||Own 51%, earning 80%|
|Location:||Southern Coast of Peru|
|Deposit type:||Cu-M-Au-Ag Porphyry|
The Pecoy Project is located one hundred and fifty kilometres northwest of Arequipa, within the Cretaceous Copper Porphyry Belt of Peru, host to the Cuajone Cu porphyry (Southern Peru Copper Corp.), the Toquepala Cu porphyry (Southern Peru Copper Corp.), the Cerro Verde Cu porphyry (Freeport-McMoRan Copper & Gold Inc.) and the Zafranal Cu porphyry (Teck Resources Limited and Mitsubishi Materials Corporation). The Property consists of 2,000 hectares held by Pecoy Sociedad Minera S.A.C.
The Project was first drilled by Pecoy Sociedad Minera S.A.C in 2009 with the completion of 3,450 metres in eleven holes. All of the holes were drilled on targets located along the margin of the system to test IP geophysical anomalies. Drill hole 2 returned the best intersections of the program with 165 metres @ 0.49% Cu (Oxide-Enrichment Zone) and 107.6 metres @ 0.41% Cu (primary sulphides in the Potassic Zone). Pembrook acquired the option to earn up to an 80% interest in the project in 2013. In 2017, Pembrook met its obligations to earn a 51% interest in Pecoy Socieded Minera S.A.C. and began working towards exercising its option to earn an 80% interest.
The Pecoy Project encompasses a large and complex porphyry system characterized by multiple porphyry and breccias events cutting basement gneissic rocks and granodiorite (Coastal Batholith). The granite porphyry system has extensive surface alteration covering an area of 1.5 kilometres by 2.0 kilometres and consisting dominantly of quartz-sericite-pyrite and silica. Leaching is apparent at the surface with abundant clay alteration. The system contains abundant multi-type quartz stockwork veining and the presence of multiple hydrothermal breccias. Surface channel rock sampling has returned up to 0.75% Cu locally with the majority of the surface exposures leached to hematite, goethite and jarosite.
The main porphyry mineralization below the leached cap consists of an oxide zone (typically azurite, malachite and chalcanthite) followed by a lower chalcocite enrichment zone and then into primary chalcopyrite, molybdenite and pyrite sulphides to depth. The centre of the main porphyry system is bounded by several large hydrothermal breccias along its margins. The South Breccia is the largest on the Project and weathers recessively. It is located largely in the lower parts of the valley bottom (1600MASL) on the south margin of the porphyry and is enriched in Cu, Au, (Ag, Mo, Magnetite).
Diamond Drilling 2014-2016
To the end of 2016, Pembrook had completed a total of 35,218 metres of diamond drilling in 53 holes for a project total of 64 holes and 38,673 metres.
Some of the highlighted intersections are as follows:
- PEC-15 478m @ 0.36% Cu, 0.260g/t Au
- PEC-16 606m @ 0.37% Cu, 0.208g/t Au
- PEC-19 340m @ 0.41% Cu, 0.098g/t Au
- PEC-41 473m @ 0.36% Cu, 0.133g/t Au
- PEC-46 399m @ 0.40% Cu, 0.133g/t Au
- PEC-49 136m @ 0.46% Cu, 0.174g/t Au
- PEC-22 529m @ 0.34% Cu, 0.013% Mo
- PEC-26 17m @ 0.83% Cu, 0.009% Mo
- PEC-32 158m @ 0.37% Cu, 0.009% Mo
- PEC-32 79m @ 0.38% Cu, 0.008% Mo
PORPHYRY AND ENRICHMENT ZONES
- PEC-13 733 m @ 0.31% Cu, 0.012% Mo
- Supergene 59m @ 0.74% Cu
- Primary 274m @ 0.35% Cu, 0.017% Mo
- PEC-20 658 m @ 0.305% Cu, 0.015% Mo
- Supergene 46m @ 0.47% Cu
- Primary 334m @ 0.33% Cu, 0.018% Mo
- Primary 96m @ 0.38% Cu, 0.009% Mo
- PEC-55 648 m @ 0.34% Cu, 0.008% Mo
- Supergene 57m @ 0.54% Cu
- Primary 234m @ 0.38% Cu, 0.009% Mo
- PEC-56 639m @ 0.33% Cu, 0.014% Mo
- Primary 126m @ 0.45% Cu, 0.016% Mo
In May 2017, Micon International Limited completed an updated Resource Estimate for the Pecoy Project.
The Inferred Resource at Pecoy now hosts an estimated 644 Million Tonnes at 0.33% Cu, 0.011% Mo, 0.050 g/t Au and 1.23 g/t Ag. The deposit remains open at depth to the east and west.
In 2016, metallurgical test work consisted of a composite from the primary sulphides on the porphyry and the South Breccia and the oxide and enrichment zones. The work showed that the mineralization will produce a clean marketable concentrate with no deleterious elements present. A summary of the results are below.
|Porphyry Conc. Grade||26% Cu||0.6% Mo||87 g/t Ag||1.5 g/t Au|
|Recovery||93% Cu||72% Mo||80% Ag||40% Au|
|Breccia Conc. Grade||27.1% Cu||68 g/t Ag||9 g/t Au|
|Recovery||88% Cu||52% Ag||54% Au|
The planned metallurgical work in 2017 is to complete additional testing of the Porphyry and South breccias sulphides to improve the recoveries for the gold and silver.
Preliminary test work has been completed on the oxide and enrichment zones indicating that there would be a 61% recovery after a 120 day leach test.
PEA (Preliminary Economic Assessment) work starting in 2017
In 2017, Pembrook plans to start progressing towards the completion of a PEA study of the Pecoy Cu,Mo (Au,Ag) deposit.
A preliminary hydrology study shows that sufficient water (assuming a 100,000 tonne/day plant) is readily available to the Pecoy Project ~8km to the west, either from the Ocona River or from gravels located closer to Pecoy.
Engineering work is underway for the various options available for road construction to the coast and a powerline study. This work is scheduled to be completed by September 2017.
In 2016, Pembrook completed a Surface Rights agreement with the local community for mining and processing. The surface lease is for 30 years with an option to re-new for an additional 30 years.