Why Additional Metallurgical Testwork ? & why core drilling...

Why Additional Metallurgical Testwork ? & why core drilling required ?
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The new assay results suggest that the serpentinite samples that were utilised for the Black Swan BFS testwork program may have a lower non-sulphide nickel (NSNi) content and a higher sulphur to nickel(S:Ni) ratio than what Norilsk Nickel Australia (NNA) reported in historical resource mine grade control data. The implications of this are that the composite samples from the disseminated resource utilised for the Black Swan BFS, while representative of the ore mined and processed in 2008/09, may not accurately represent the current Black Swan BFS open pit mine plan. The disseminated open pit drilling results recently obtained by Poseidon and the historical NNA resource mine grade control data set both utilised RC drilling to obtain the samples for NSNi assays.
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It is possible that the RC drilling process, which pulverises a large proportion of the drill core into ultra fine particles, may result in reporting elevated NSNi assays because of the considerable particle surface area that is generated from the RC drilling mechanism.
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The extremely large particle surface area generated, which is exposed to the elements for many weeks prior to the NSNi assays being completed at the laboratory, may lead to some oxidation of the nickel sulphides, thereby potentially reporting elevated NSNi results.
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This aspect will be assessed by using diamond drill core for the upcoming metallurgical sampling program.