Ann: Further Extensions to High-Grade Nickel-Copper Sulphides, page-43

yes same techniques a lot more fined tuned these days than years ago - the Law of nature as such - time and price

I spoke with the geo being he's found me here won't go into too much detail of the conversation !
all I will say is the slow and methodical approach the way they are doing it is a good thing and that its probably a matter of waiting for the actual resource they find from the market most likely why its not moving

cheers