Modern Mining February 2016

MINING News

“Unexpected challenges” at New Liberty tional performance of the gravity circuit and further optimising CIL leach kinet- ics, with various options being evaluated and systematically implemented in order to improve overall plant performance to within design specifications.

Gold production achieved for the calen- dar year 2015 was 17 172 ounces, against a target of 27 000 ounces, and 3 663 ounces of gold have been produced to date in 2016, with production since mid-Decem- ber hampered by issues experienced during the final phases of plant commis- sioning. Performance from the gravity circuit of the plant has not yet reached design specifications, resulting in overall gold recoveries of approximately 70 % throughout December 2015 and early January 2016. Commenting, David Reading, President and Chief Executive Officer of Aureus Mining, said: “The commissioning phase of New Liberty has brought some unex- pected challenges; however, the recent progress being made and improved performance of the process plant are encouraging. I am confident that the various process improvements that our experienced operations team are system- atically implementing will continue to improve the overall plant performance towards design specifications.” 

Aureus Mining Inc, listed on the TSX and AIM, has provided an operational update (issued 22 January) for its New Liberty Gold Mine in Liberia. The mine – commis- sioned in 2015 – suffered a crusher failure in October which halted production at the mine for a short period. Since the resumption of processing operations at New Liberty on 30 October 2015, the ball mill has been operating at an average of 82 % for 81 days (to 22 January) of its designed capacity, including planned downtime for ongoing optimisation. While the criteria for the declaration of com- mercial production have been reached, Aureus has experienced issues during the final phase of commissioning in the grav- ity and CIL circuits of the plant, affecting plant recoveries and resulting in an impact on cash flow. It says it therefore does not feel it is prudent to officially declare com- mercial production at this point. The company continues to focus on fine-tuning and improving the opera-

Aureus say it is anticipated that plant performance will improve to design levels by the end of Q1 2016, when the company intends to declare full commercial produc- tion at New Liberty. Mining operations at New Liberty are progressing, with fresh ore run of mine (ROM) stockpiles currently standing at 83 509 tonnes at a grade of 2,78 g/t and oxide and transitional stockpiles at 75 248 tonnes at a grade of 1,35 g/t. To date, the process plant has processed 386 262 tonnes of ROM fresh sulphide ore and lower grade oxide material resulting in 19 shipments of gold doré from New Liberty for smelting and refining at the MKS PAMP refinery in Switzerland, totalling 20 835 ounces of gold.

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