The near-surface resources of the Lady Julie Gold Project (LJGP) lend themselves to open pit mining with equipment that is widely proven on the Eastern Goldfields, namely hydraulic excavators and rear dump trucks. Blasting is used sparingly to condition the rock for extraction with powder factors varying according to oxidation status.
Magnetic propose to develop a gold mining operation incorporating the Lady Julie North 4 (LJN4), Lady Julie Central 9 (LJC) and Hawks Nest 9 (HN9) deposits.
The order of extraction is LJC, LJN4 and finally HN9.
Mining Method
The mining method is intimately linked to geology/grade control, and planned drilling and blasting practices as for any hard rock open pit. The selected method is usually a compromise between selective mining of ore and waste, the expected mining equipment, and mining costs:
• The mining of the ore zone is planned at a nominal 5m bench height using a back-hoe excavator mining on two nominal 2.5m flitches. This will allow mining selectivity between ROM grade ore, low grade ore and waste boundaries, as long as mining of gently dipping ore zones is always from hangingwall (HW) to footwall (FW). This will allow mid-sized mining equipment to be used efficiently.
• Waste will be mined in 5m benches.
• A key part of the mining method is to use angled RC grade control to identify the economic (as opposed to purely geological) HW and FW contacts. The RC holes will also identify ........