Sep 4 2015
Lydian International Limited ("Lydian" or "the Company") reports that results to date of its continuing metallurgical testing program and a blast fragmentation study demonstrate potential to favorably reduce initial capital costs and future operating expenses at its 100% owned Amulsar Gold Project in Armenia.
Based on the projected outcome from this year's metallurgical testwork program and assessment of the rock quality in the ore body, Lydian plans to eliminate three of five cone crushers from the secondary and tertiary circuits and to reduce the double deck screens from five to three. The primary gyratory crusher will be replaced by a jaw crusher and the design nominal crush size will be increased from 12.5 mm to 19 mm. These revisions are expected to significantly reduce equipment requirements, the plant's structural footprint and energy consumption, while maintaining crushing capacity at 10 million tonnes per annum.
Howard Stevenson, Lydian's President and CEO, stated, "Value engineering has been ongoing for six months and continues to find opportunities to reduce initial capital costs and future operating expenses. Our ability to re-design the crushing plant is very positive news and is as good as we could have anticipated at this point in our value engineering program. Our most recent technical report included $75 million of direct costs for the crushing plant. Cost estimates for the re-designed crushing plant and other optimizations identified through value engineering will be completed as part of an updated technical report and will be reported as soon as they are finalized." Mr. Stevenson added, "Increasing the crush size, reducing reagent consumption and optimizing solution flow rates will also generate positive expense reductions and environmental improvements."
The objective of the metallurgical testwork is to provide comparative recovery and reagent consumption information for material crushed to P100 19 mm (100% passing through 19mm) and P100 12.5 mm. A total of 13 composites were defined and used for 30 column leach tests. Column test results from this ongoing program show average gold extractions are trending consistent with prior column tests performed by the Company as reported in the 2015 Amulsar NI 43-101 Feasibility Study, dated May 16, 2015 ("2015 Technical Report"), which averaged 90%. Importantly, results also indicate no statistical difference in leach kinetics or final gold extractions between composite samples crushed to P100 19 mm and P100 12.5 mm. The 2015 Technical Report assumed an optimal crush size of P100 12.5 mm.
Current testwork indicates reagent consumption will be significantly lower and solution flow rates can be reduced from previously reported amounts. Preliminary solution assay results confirm a rapid rate of gold extraction using lower reagent concentrations than in earlier test programs. The majority of gold was extracted within 14 days with maximum extraction typically occurring in less than 60 days. SGS North America Inc. is performing the testing at its laboratory in Tucson, Arizona.
A blast fragmentation study and subsequent classification of rock quality distributed in the geo-metallurgical model of the deposits indicate 65% to 95% of the ore is highly fractured with a "poor" rock quality, and less than 5% of the ore is of "good" rock quality. Rock quality classification was not included in the 2015 Technical Report, and all ore was assumed to be of "good" rock quality. The outcome of this study supports Lydian's plans to re-design the crushing plant and is also expected to contribute to reducing future blasting and crushing operating expenses.
A revised technical report will be issued upon completion of the Company's value engineering program which is to be completed during fourth quarter 2015.
Source: http://www.lydianinternational.co.uk/