Midas Gold Corp. announced that it has commenced feasibility level metallurgical testing, which is being conducted as a critical path item in advance of preparing a feasibility study on its Stibnite Gold project.
This work is expected to continue through the second quarter of 2017 and is intended to provide sufficient supporting process information to advance the Project through completion of a feasibility study.
"The commencement of the metallurgical testwork required to support a feasibility study represents another milestone in the advancement of the Stibnite Gold Project," said Stephen Quin, President & CEO of Midas Gold Corp.
"The purpose of undertaking these metallurgical programs, and advancing them all the way through pilot scale testing, is to provide us with the confidence required to support a feasibility study, while the incorporation of geo-metallurgical modelling in 3D should provide a higher degree of predictability in metallurgical outcomes for the Project".
Initial Metallurgical Objectives
The purpose of the metallurgical testing is to evaluate the opportunities for Project enhancement identified during preparation of the Preliminary Feasibility Study ("PFS"), the results of which were announced on December 14, 2014, to further increase technical confidence associated with the Project to levels appropriate for a feasibility study, and to improve the quality of design data for engineering studies to be undertaken as part of a feasibility study.
Initial studies are designed to further enhance the positive design and performance of the crushing, grinding and flotation circuits set out in the PFS and will be conducted at SGS Canada's ("SGS") Burnaby laboratory.
The final flowsheet will be confirmed through additional locked cycle and bulk flotation testing at SGS, and ultimately through a mineral processing pilot plant at Blue Coast Research Ltd. in British Columbia. Improvements in crushing, grinding and flotation recoveries could potentially reduce capital and operating costs, thereby enhancing Project returns.
Pressure Oxidation Testwork
The pressure oxidation testwork will include extensive testing on the processing of the gold-bearing sulphide flotation concentrate produced during the flotation testwork discussed above. A batch POX program is planned, starting later in 2016, once sufficient concentrates have been generated.
This batch testwork will be followed by two phases of continuous pilot plant POX testing. The first phase of continuous POX testing will fine-tune process design and will use a composite representing the projected first three years of mine production. The second phase will test the final design conditions on several composites of material originating from different sources throughout the Project.
The selection of a preferred laboratory from those available in the United States and Canada will not be made until the required concentrates have been produced and laboratory availability has been confirmed. This phase of testing will also include the development of design information for all processes downstream of the POX circuit.
A geo-metallurgical work program is being carried out in parallel with the flowsheet development testwork. This geo-metallurgical testwork will link Project geology and proposed mine plan with process performance, using the extensive and detailed geological, geochemical and mineralogical data collected by Midas Gold linked through algorithms to mineralogical and process performance data.
This data includes detailed logging of rock type, alteration and mineralogy in core collected by Midas Gold since 2009, assisted by extensive multi-element geochemical analysis and advanced scanning techniques that assist in identifying particular styles of alteration and mineralogy much more precisely.
With this detailed, multivariate information available in 3D space, the mineral resource model can then be used to evaluate variability in process response throughout the various deposits that comprise the Project, as well as better predict process performance through the projected life of the Project. Work started on this geo-metallurgical program in July and is expected to be complete late in the first quarter of 2017.