Newstrike Capital Reports In-Pit Heap Leach Gold Recoveryhttps://newstrikecapital.com/news-releases/2014/index.php?&content_id=151
Newstrike Capital Reports In-Pit Heap Leach Gold Recovery
At The Ana Paula Project In Guerrero, Mexico Vancouver, B.C. June 26th, 2014 - Newstrike Capital Inc. (TSXV: NES) (“Newstrike” or the “Company”) reports a column leach metallurgical result from a composite sample supporting heap leach extraction potential within the low-grade breccia zone at Ana Paula.
Richard Whittall, CEO, commented: “Our 2013 metallurgical testing program confirmed a conventional, low-risk approach at Ana Paula with strong gold recoveries. This specific column leach result adds an extremely encouraging new dimension to the project. Heap leaching has the potential to lower processing costs and provide an additional source of revenue through the recovery of gold from our mineralized waste. We plan to investigate the size and scope of this opportunity within Ana Paula’s floating cone pit and the potential for a reduction in the strip ratio and expansion of the conceptual pit. Combined with last year’s testing, this new metallurgical result will provide valuable input to the Preliminary Economic Assessment currently in progress as well as for future studies.”
Although sulfide mineralization at Ana Paula is not generally amenable to heap leaching, significant gold recovery at 84.1% was obtained from a representative composite sample from two drillholes, AP-11-36 and AP-13-213 selected from within the Maiden resource floating cone pit (Newstrike press release May 8, 2013). The representative composite sample was selected to test the leaching capability of the low grade breccia zone, a predominantly intrusive unit located in the southwest portion of the floating cone pit and separate from the high grade breccia zone. Composite 4 is from a sample of altered intrusion that has not been fully delineated by drilling and that displays a level of oxidation greater than compared to most of the Ana Paula deposit. The sample was prepared from 56.28 metres of drill core, weighing about 88 kilos when submitted for metallurgical testing to internationally recognized and accredited SGS Metcon/KD Engineering of Tucson, Arizona.
Summary of Results - Locked Cycle Column Testing | Test No. | Leach
Day | Calc. Head (1)
Assays (g/t) | Residue (2)
Assays (g/t) | kl of Solution per
tonne of Ore | Extraction (%) | Reagent Consumption (kg/t) | |
| Au | Ag | Au | Ag | |
| Au | Ag | NaCN | CaO
| |
| Composite 4 | 91 | 0.57 | 3.86 | 0.09 | 3.37 | 2.95 | 84.10 | 14.60 | 0.19 | 3.62
| |
Remarks
(1) Calculated Head assays for columns are net content extracted plus the content in leach residue screen fractions.
(2) Residue screen assays are calculated based on weight distribution and screen assays
The Table summarizes results from the column leach test. Conclusions from this testing indicate that most of the gold was extracted in the first 10 days, and that the maximum extraction obtained was 84.1% on Composite 4. The composite sample showed the highest cyanide soluble gold content in the head assay and may be amenable to gold recovery by heap leach process.
Other conclusions from this test work indicate a low sodium cyanide consumption at 0.19 kg/tonne and moderate calcium oxide (lime) consumption at 3.62 kg/tonne. Good gold and silver extraction correlations were observed between the results from the bottle roll testing and the column leach testing. Further Bond Impact Crusher Work Index and Bond Abrasion Index studies will be conducted on Composite 4.