Mining output is currently dominated by the Starlight underground mine with supplementary, free on surface low grade stocks providing a blended feedstock to the plant.
Vast stockpiles remain at Fortnum and a ‘right sized’ Starlight delivering lower tonnage to the Fortnum mill at a higher grade will provide a superior economic outcome.
Underground Methodology
* In large disseminated orebodies sub level caving, sub level open stoping or single level bench stoping production methodologies are used.
* In narrow vein laminated quartz hosted domains a conservative narrow bench style mining method is used.
* In narrow flat dipping deposits a Flat Long Hole process is adopted (with fillets in the footwall for rill angle) and or jumbo stoping. Minimum mining widths have been applied in the various mining methods.
* Depending upon the style of mineralisation, sub level interval, blasthole diameters used and if secondary support is installed, total dilution ranges from 15 to 35%.
* Minimum mining widths have been applied in the various mining methods. The only production style relevant to this constraint is ‘narrow stoping’ – where the minimum width is set at 1.5m in a 17.0m sub level interval.
* Mining operational recovery for the underground mines is set at 100% due to the use of remote loading units as well as paste filling activities. Mining recovery is not inclusive of pillar loss – insitu mineralised material between adjacent ........
