Yes - however, it should be pointed out that ultramafics...

Yes - however, it should be pointed out that ultramafics (dunite, peridotite) have a high level of nickel present - in the silicate minerals (olivine). So it is no surprise that the drilling that has cut the entire intrusive body is highly anomalous in nickel. The nickel trapped in the silicates is not recoverable by flotation to a sulphide concentrate - so it just goes to the tails. So the question then should be - of the nickel in the rock, what % of this is present in sulphides and hence recoverable. Whole rock assay will just tell you what is the nickel concentrate of the rock and not what mineral species the nickel is present in.