I have to say that I agree. Ore that's marginal for cut-off now...

I have to say that I agree.

Ore that's marginal for cut-off now becomes part of the resource.

I can do some simple analysis on feasibility of the production metrics required.

So we drop the cut-off from 0.18 g/t to 0.1 g/t. That boosts the resource to 3.83 Moz.



Next I need to work out how many ore sorters they would need.

The ore sorter processes ore at 3,600 tph.



Now let's make some other assumptions:

• 60% of the resource converted to reserve. This is the portion of the resource they are likely to be able to define as part of a pit shell from looking at studies for other mines.
• They have achieved 76% recovery in preliminary bottle roll heap leach test work.
• 15 years mine life.
• Victoria Gold used 7,140 hours / annum operating hours for equipment in their 2012 feasibility study (see below)

Those assumptions result in:

• approximately 166 koz pa production from the mine
• 12.5 Mt of rock needs to be processed per annum
• 1,754 tonnes of rock are processed per available hour

1,754 tonnes per hour is comfortably within the operating parameters of the ore sorter.



Now the smart thing to do would be to only ore sort the ore at the margins of cut-off. Ore selection would be done through grade control-drilling. So they would perhaps only ore-sort less than 25% of the ore [theory is that less operating costs (power, spares, etc) for running the ore sorter].

This is the current block model ( for the 3.3 Moz resource ).