Why Good Grades are Important, page-11

The TOMRA XRT 2.0 sorting machine can sort particles of up to 100mm at a rate of 1000 tph for one machine.

Navchabs sorting line is up for 80-90 percent of the time and has been running since 2016. The Navchab mine uses a cut off of 1.5, with particle size of 20-30mm at a sorting rate of 200 tph (tonnes per hour):



We have currently 0.3 grams per tonne, for 4.7 ,million OZ.

A TOMRA XRT 2.0 can sort 1000 tph with particle size of 100mm

Assuming the machine runs for 20 hours per day, it can sort 20,000 tpd.

@ 0.3 that is 190 oz per day, or 68000 oz per year (rough calculations)

So if Estelle had two TOMRA XRT 2.0 ore sorting machines, that would be 68000 (per machine) x 75% (recovery rate) x 2 machines = 102000 oz per year.

I still think this is a reasonable rate of initial production and we Probably better if the resource size comes down, becomes indicative and the grade goes up.

1 million 0Z at 0.5 grams per tonne would give an initial mine life of 10 years.

Using ore sorting to bring up the cutoff grade actually means that a lot more earth has to be moved:

518 million tonnes of earth for 0.15 g/t and a 4.7 moz resource

vs

57 million tonnes for cutoff of 0.45 g/t 1.1 moz resource

They are using the "idea" of the ore sorting tech to bring up the inferred resource, when the indicated and feasible could actually be a LOT lower.

I am struggling to work out if our resource has actually really grown at all, or if they have just found a way to bring the "possible" cutoff rate down, so to give themselves more options / cash / wealth. The low-grade resource has increased (1.5 cuttoff / 0.18 cutoff), whilst the resource at the upper grade is has actually come down / been diluted:


from 4.7 million upgrade


from maiden 2.5 million announcement:



@kduvey