Modern Mining June 2018

MINING News

Cradle Arc announces maiden ore reserve for Mowana

The processing plant at the Mowana mine (photo: Cradle Arc).

The total costs of the DMS plant and associated upgrades, which have been included in WAI’’s model, are expected to be approximately US$20,0 million. “The successful completion of the ore reserve estimate and upgrade of the mineral resource estimate under- pins the significant scale and long term commercial value potential of Mowana,” comments Kevin van Wouw, Cradle Arc’s CEO. “WAI’s independent assessment further supports our recently imple- mented accelerated development plan announced in April 2018, which we antic- ipate enabling us to reach steady state production and positive cash flows more rapidly, in addition to enabling manage- ment to make the final decision regarding the implementation of the DMS upgrades as we seek to ramp-up production and ultimately strengthen the value funda- mentals of Mowana. “Mining operations at Mowana have been ramping-up over the last six weeks and we currently have two mining units operating full time in the open pit. These works will support a doubling of ton- nage to the existing processing plant and the planned integration of DMS will then enable the plant to produce an average of approximately 21 000 tonnes of copper per annum, and up to 27 000 tonnes of copper in year 3, over a newly extended 14-year life of mine.” 

AIM-listed Cradle Arc has announced a maiden JORC (2012) ore reserve for its 60 %-owned, open-pit Mowana copper mine located in north-east Botswana. On 3 April 2018, the company announced its maiden mineral resource estimate (MRE) for Mowana, completed by Wardell Armstrong International (WAI), and said it had commissioned WAI to produce a maiden JORC (2012) ore reserve, draw- ing together the technical data from the various positive work streams completed in respect of the planned implementation of the Dense Media Separation (DMS) pre- processing technology.   The MRE previously announced has now been further updated followingWAI’s work on the ore reserve estimate, with a portion of the inferred resources being transferred into the higher confidence indicated resource category. The ore reserve (proved and probable) comprises 31,8 Mt at 1,17 % Cu for 370 800 tonnes contained copper metal, based on the DMS mine plan. The MRE puts mea- sured and indicated resources at 55,0 Mt at 1,17 % Cu for 640 000 tonnes of contained copper, representing an increase of 37 %. Following the commencement of the company’s accelerated development plan at Mowana in April 2018, mining opera- tions have been ramping-up and two mining units are currently operating full time in the open pit, allowing access to

ores below the 960 level. In mid-May 2018, the first 40 000-tonne blast of transitional ore was produced in line with the mining reserve plan. Following commencement of process- ing of these transitional ores, Cradle Arc confirms that the recoveries are within the range expected. The parameters included in WAI’s work with regard to the planned DMS upgrades, are based on the purchase, installation and commissioning of two, 150 t/h, DMS mod- ular units and associated ancillary circuits and equipment. ThescopeoftheDMSupgradeprojectwill also include a review of the Environmental and Social Impact Assessment (ESIA) and the mine’s Environmental Management Plan. Upgrades will be required to the tail- ings system to ensure efficient and effective operations. These will include the addi- tional drilling of two 100-inch water supply boreholes and the inspection and refurbish- ment of the current operational borehole network. Certain plant units will need to be upgraded such that they are aligned to the requirements of the DMS plant and able to cater for the additional tonnages required on the dry section, as well as the increased holding capacity required for concentrate thickening and tailings disposal. Controls will also be enhanced for maximum effi- ciencies throughout the plant.

4  MODERN MINING  June 2018