A Preliminary Economic Assessment (PEA) was filed in 2008 and updated in 2011 for which the estimated resources at the time were used for the technical and financial evaluation of the project. These now downgraded to historic* resources for the Ferguson Lake mineralized body include the East Zones, West (Main) Zone, and West Extension Zone.
Previous mineral deposit modeling and re-examination of historic resources for the main West Pit and West Extension Zones has shown that enlarged pods of better grades of BM and PGM metals mineralization are present within massive to semi-massive sulphide lenses and stringers within zones, and have have thicknesses between two and tens of metres.
Very thick (up to 71.3 m) PGM mineralization zones associated stringer/disseminated sulphides occur in the footwall structures of the northeast-dipping gabbro units in 10 mineralized zones. Previous assay results show high-grade PGM values up to 103g/t palladium and 43.36g/t platinum in these low-sulfide zones. Selected previous assay results are presented in Table below:
* These are now historical estimates provided for information only, original source Starfield Resources Inc. Nov. 2011, Technical Report filed on SEDAR but now outdated, no longer valid and not to be relied upon as being 43-101 compliant. A significant re-evaluation at today’s gold prices and economic conditions would have to be completed to upgrade this historic estimate as current mineral resources.
The resources were assessed based on block models of the undiluted massive sulphide sheets and lenses within the West (Main) Zone and polygons in the East and West Extension Zones. The economic analysis for the PEA was based, in part, on Inferred Resources classified at the time of filing, and is preliminary in nature. The resources were estimated at Ni+Cu+Co NSR cutoff values of C$75 for open pit and C$110 for underground.
Metallurgical recovery for the evaluation included only nickel (94%), copper (97%), and cobalt (89%), where no palladium and platinum were credited. Recent metallurgical tests by Canadian North Resources Inc. on mineralized samples have reported up to 95% recoveries for previously uncredited palladium and platinum.