Porphyry

The first stage of Saracen Mineral Holdings ambition to become a mid tier Australian gold producer commenced with the re-commissioning of the old Porphyry-Edjudina working at its Carosue Dam Gold Project at South Laverton in the Eastern Goldfield Region of Western Australia.

Five Open Cut Mines, Including the Porphyry-Edjudina Mine, Make up the Carosue Dam Project
The Carosue Dam Project involves the operation of five open cut gold mines beginning with the Porphyry-Edjudina Mine. A mine that has a history of producing a total of 144,000 ounces of gold the last time it was operational. The beginning of work at the Porphyry-Edjudina mine coincided with the wet commissioning of the Carosue Dam Gold Processing Plant where surface stockpiles and Porphyry ore are milled. The other mines involved in the project include; Wallbrook, Deep South, Enterprise and Whirling Dervish. All are to be mined over the next three to five years.

New Village Accommodation Built at the Porphyry-Edjudina Mine Site
The Carosue Dam Project employs about 200 contractors and staff, with separate accommodation being built in 2011 to house an additional 80 people at Edjudina, close to the Porphyry-Edjudina operation.

Underground Mine Worked via a Room and Pillar Method
In the 1980's, mining had been carried out at Porphyry by Edjudina Gold Mines. This operation included an open pit and underground mine that was mined using a room and pillar method. It was a shallow working following a dipping, near surface, lode. A lode that had previously been worked from the surface. The underground development followed the ore, a practice that resulted in quite low capital costs. However, underground mining ceased at the Porphyry-Edjudina Mine in the late 1980's because of the low gold price at the time.

Porphyry-Edjudina Mine Needed De-Watering Before Work Could Restart
Recent activity at the Porphyry-Edjudina pit required substantial de- watering before any work could commence and this revealed the existing portal and adits into the previous workings. A bore was sunk into the deepest area of the mine to pump the water out of the underground workings before a feasibility study could be undertaken as to the likelihood of it re-opening. Underground remedial work would require improvements to the decline, a hanging wall ventilation drive and a secondary means of egress.

Large Underground Resource at the Porphyry-Edjudina Mine
It is expected that any ongoing underground mining will follow that practised during the 1980's to best exploit the underground resource. The underground resource at the Porphyry-Edjudina Mine is presently set at 1.3 million tonnes of ore grading at 4.1 grams a tonne that would realise 171,000 ounces. Reserves are put at 634,000 tonnes grading at 3.4 grams a tonne that would return 70,000 ounces of gold.
Same Haulage Road Links All Mines to Carosue Dam Gold Processing Plant
The haul road was upgraded in 2010 with a new section being built between the processing plant at the Carosue Dam site and the Porphyry- Edjudina Mine, a distance of 48 kilometres. The same haul road connects the other four mines to the same processing plant.
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