I find this interesting because of the metallurgical aspect. Any property that is entirely recoverable by gravity techniques may have enhanced economics.
I have run into a few like this and they aren't entirely obvious. One I saw in Manitoba was a pure quartz vein with very rare VG. Yet on relatively light grinding, 80% came out in the jig. Gold economics isn't what people think some times. In this mentioned case they narrow quartz vein, encased within very hard rock may have had 1/2 the mining and development costs of many other similar-looking veins.
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Freegold Recommences Processing of Bulk Samples with
Enhanced Gravity Plant at Golden Summit
June 13, 2008 (Vancouver, BC) -- Freegold Ventures Limited ITF/TSX, is pleased to announce the resumption of its seasonal bulk sampling program at the Golden Summit project located outside Fairbanks, Alaska. Commencement of this first full processing season follows the recent purchase and installation of additional processing equipment to enhance the crushing and grinding capabilities of the Company's gravity-based gold recovery plant.
The decision to expand the plant was made upon the completion of comprehensive metallurgical testing over the winter which showed that significantly higher gold recoveries can be expected with smaller-sized material processed through the plant.
Recoveries ranging from 80 to 95% have been achieved on 17 bulk sample composite samples that have been reduced to a particle size in the laboratory that is reflective of the new crushing and grinding capabilities of the plant.
With composite head grades ranging from 1.9 g/t (0.055 oz/ton) to 44.6 g/t (1.3 oz/ton), the high gravity recoveries seen across all sample grades reconfirms the coarse nature of the gold seen in the previous test work and in the initial gravity concentration work.
The primary purposes of the bulk-sampling program at Golden Summit are to determine the continuity of gold mineralization found within numerous gold-bearing shear zones that were discovered and delineated through trenching and shallow RAB drilling over the past two years, and to generate cash flow from the on-site gravity concentration of the gold found in this material. Following the receipt of permits in May 2007,
Freegold commenced construction of a portable gravity-based gold concentration plant capable of processing up to 1,200 tons of mineralized material per day. The plant was transported to Alaska last summer and following assembly, became operational in September 2007. Following approximately 4 weeks of increasing through-put up to its design capacity, the processing operations were halted in October with the on-set of freezing temperatures.
As the Company was unable to source a secondary crushing plant last year, the primary crushing circuit was modified to operate in a closed loop to try and achieve the required minimum crush size. Unfortunately, this configuration did not consistently generate the required feed size which in turn negatively impacted the gold recovery and processing rates. Gold recovered in concentrates during the initial processing period were utilized for subsequent test work to optimize re-grind and final concentration methods. Although initial recovery was below expectations given the insufficient crushing capability, the majority of the gold remains contained within the coarse tailings that were separated and stockpiled adjacent to the plant, and which will be the first material to be processed this season with the newly modified plant. Further details on the bulk sampling program, including an overview of the location, volume and grades of materials sampled to date, and an overview on the sampling locations and volumes estimated for 2008 will be provided in the Company's next release.
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