The Wolfram Camp deposit is a quartz-rich pipe-like type deposit, with major element zoning around the pipes (Plimer, 1974). Similar to other pipe-like Mo- W-Bi(+/-Sn) deposits in the Tasman Geosyncline of Eastern Australia, it is hosted in the greisen altered margin and roof zone of a granite mass. Quartz greisens commonly form a rim of several metres wide around quartz pipes, with variable and generally lower grade mineralisation.

The Wolfram Camp Mineral Field is dominated by the Ootann Supersuite granite intrusives and related greisen alteration and mineralisation. Greisens are apparently developed at the upper contacts of intrusives usually capping apophyses, where late stage (post intrusive) gases and volatiles naturally accumulated, and are in contact with overlying hosts, in this case the sediments and volcanics of the Hodgkinson Formation.

Alteration and mineralisation are considered to be related to a post intrusion (or very late stage) aqueous mineralising phase or phases, which produces a greisen. The mineralisation consists of erratic pods, pipes and veins, in which the majority of sulphide, wolframite and molybdenite is contained, scattered throughout the greisen zone, over a width of ~50 m. The greisen extends up to the contact but not into the host rocks.

Morton and Ridgway (1944) noted that in most of the pipes mined to that date wolframite predominated whilst in some instances (Mulligan, McIntyre, Nil Desperandum) molybdeni ........

The current open cut is approximately 800m along strike.In general the pit is advanced with benches extended out to the design pit shell on the north-south sides, and is deepened in 3-4 sectors along strike.

Drilling and blasting will be carried out by a specialist D&B contractor.Blasts are planned over 5m bench heights,with combined ore and waste partitions.The individual models determined from GC drilling are used to delineate different categories of material for mining, based on cut-off levels of 0.07, 0.12 and 0.3% WO3.Separate models for each blast area also built up.

Blastholes, 89mm in diameter, are drilled on 2.7 x 2.4 m pattern.Plastic hoses are placed in high grade holes,which are not blasted.This helps against excessive fragmentation of wolframite, and the hoses provide an estimate of blast displacement.All blasting generally uses ANFO. Subsequent to blasting, the positions of the plastic hoses are re-surveyed, and the original ore/waste delineations are modified according to the measured displacements, as well as by visual assessment by geologists.Different colour ribbons are used to demarcate the different ore/waste categories.

Digging of material is done with a backhoe excavator, sitting on top of the broken muckpile, loading 40t trucks.Digging is done in 3 vertical passes: the first for the heave above the original bench floor, the second for the 0-2.5m depth cut and the third for the 2.5-5m depth cut.Ribbons are marked up ........

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