5 million tonne or more stockpile, page-25

Sometimes zzedzz you just need to acknowledge you are wrong.

Firstly a 2:1 stripping ratio is excellent compared to a few of the places I've been. 2:1 means 2bcm of dirt to 1bcm of ore. The ore is probably a little more dense than the dirt so the mass ratios will be even more favourable.

Secondly, mining is not the same as manufacturing where higher than necessary inventories are an unnecessary cost burden. Particularly for a start up mine, who knows what surprises there may be down in the dirt. Remember the kerfuffle about the JORC calculations? Well the final arbiter of the resource will be the tonnes of truth dug out of the ground. Better to know what is there now than discovering issues when a hungry treatment plant is demanding to be fed.

Thirdly, the ore is a natural product and is naturally variable. The ore stockpile should subdivide into several piles of different ore types. The plant will need ore supplied as a blend to keep it happy. As the plant operators gain experience and as the plant is tweaked for optimum performance, the required blend will be changed to cater for what is coming out of the ground. Initially though, the plant operators need to select ore to optimise plant performance.

Fourthly, between the dirt and the ore there will be some intermediate stuff, too low grade to treat economically at first. However once out of the ground it gains value because it no longer has to be dug up. Putting this stuff aside as a low grade stockpile gives the potential for more profits later in the life of the mine. Ore bodies are diminishing resources and as they diminish, low grade can be used to feed a plant that has paid for itself many times over.