KBL Mining has estimated a maiden probable ore reserve for the DE deposit at its Sorby Hills Lead-Zinc-Silver Project near Kununurra in northern Western Australia. The probable reserve is 2.4 million tonnes @ 5% lead and 54 grams/tonne silver, applying a cut-off of 2% lead.
The JORC-compliant reserve was prepared by MEC Mining and estimated through the assessment of modifying factors on the indicated resource component of a resource estimate and model completed in mid-2013. The reserves are the basis for detailed mine planning of an initial 10 year open cut operation annually processing 400,000 tonnes as outlined in the Sorby Hills’ pre-feasibility study (PFS).
The resource estimate for DE is now 5.8 million tonnes @ 3.5% lead, 0.4% zinc and 41 grams/tonne silver, applying a cut-off of 1% lead. The resource estimate includes the ore reserve and consists of both indicated and inferred resources. The revised estimate and model of the DE deposit was produced in mid-2013 by Breakaway Mining Services.
An initial global resource for all the deposits within the 10km-long Sorby Hills’ mineralized trend was produced in 2011 that totaled 16.7 million tonnes @ 4.5% lead, 0.7% zinc and 52 grams/tonne silver.’
Sorby Hills, which is 75% owned by KBL and 25% by Henan Yuguang Gold & Lead Ltd, with KBL as JV manager, comprises 13 discrete high grade deposits within a linear north-south mineralized trend extending over a 10km strike length. Stage 1 of the project has been designed on the DE and C deposits accounting for 1.5km of the mineralized trend, or 27% of the global resource.
KBL has completed a PFS for stage 1, based on a conventional open cut mine and sulphide flotation concentrator operation, which generates robust financial returns. Initially higher grade ore if planned to be mined and processed directly through lead concentrator. There is potential in later years to mine lower grade ore at a higher production rate and processed through a heavy media plant before final concentration.