Copper Fox Reports Positive Results from Solubility Testwork Outlines Plans for Van Dyke Copper Project
- Positive test results indicate copper recoveries ranging from 8.6% to 96.5% in the Oxide zone and from 11.7% to 72.2% in the Transition zone within the 72-hour leach period.
- The geotechnical work program aims to support an updated plan for the decline to access the Van Dyke deposit and determine if additional data is needed to support a Preliminary Feasibility Study for the underground development.
- None.
Calgary, Alberta--(Newsfile Corp. - November 15, 2023) - Copper Fox Metals Inc. (TSXV: CUU) (OTCQX: CPFXF) ('Copper Fox' or the 'Company'), through its wholly owned subsidiary Desert Fox Copper Inc., is pleased to provide an update on results of the mineral solubility testwork and commencement of a geotechnical study of the Gila Conglomerate on its
The mineral solubility/mineralogical testwork was completed to better understand the dissolution rates of the various copper minerals, the mineralogical variability across the Van Dyke deposit and the chemical changes that occur due to the leching process.
The geotechnical work is focused on collecting additional data to better characterize the strength of the Gila Conglomerate to support an updated plan for the decline to access the Van Dyke deposit. The geotechnical work program will be completed by Call & Nicholas Inc. to determine if additional data is needed to support a Preliminary Feasibility Study ('PFS') level study for the underground development. Highlights of the mineral solubility testwork are:
Highlights
- Copper recoveries ranged from
8.6% to96.5% (average65.1% ) in the Oxide zone and from11.7% to72.2% (average30.4% ) in the Transition zone within the 72-hour leach period. - Recoveries for acid soluble copper ('ASCu') ranged from
28.9% to98.0% (average81.5% ) in the Oxide zone and from27.1% to97.1% (average59.4% ) in the Transition zone within the 72-hour leach period. - Recoveries for cyanide soluble copper ('CNCu') ranged from
0.0% to72.0% (average25.1% ) in the Oxide zone and from0.7% to37.2% (average20.8% ) in the Transition zone. The CNCu recoveries in some samples exceed the expected recovery from CNCu soluble copper minerals. The reason for the excess CNCu recovery, while positive, is being investigated. - Pregnant Leach Solution ('PLS') grades ranged from 0.19 g/l to 15.30 g/l copper. PLS copper grades are a function of higher total ASCu and CNCu concentrations.
- Call & Nicholas Inc. has been retained to complete the planned geotechnical program.
Elmer B. Stewart, President and CEO of Copper Fox stated, "The recent permitting and financing of the Florence Copper Project, located in Florence, Arizona by Taseko Mines Limited, is considered a significant event for other ISCR projects in Arizona, congratulations to Taseko. The test results for our Van Dyke copper project are positive and encouraging, indicating rapid solubility of the acid soluble copper minerals and enhanced solubility of the cyanide soluble copper minerals within the 72-hour leach period. The acid soluble and cyanide soluble copper that was not recovered within the 72-hour leach period is expected to be recovered over a longer leaching period as is expected in the in-situ leaching process."
Van Dyke Deposit
The thickness of the "leach cap" overlying the Van Dyke oxidized copper deposit is characterized by variable concentrations of clay, hematite, limonite, jarosite and goethite, and typically contains less than 100 parts per million ('ppm') copper and ranges in thickness across the deposit. The Van Dyke copper deposit consists of three distinctive mineralogical zones: an upper Oxide zone (primarily malachite. azurite, chrysocolla and native copper (possibly cuprite)) underlain by a Transition zone (primarily chalcocite with lesser malachite, chrysocolla and azurite) underlain by the primary sulphide zone (primarily chalcopyrite with lesser concentrations of chalcocite and bornite).
Mineral Solubility Testwork
Understanding the chemical and mineralogical changes that occur from the initial injection of the leaching solution until recovery of the copper bearing leaching solution (referred to as the PLS) is a fundamental aspect of ISCR projects. The 65 samples selected for mineralogical/mineral solubility testwork were collected from drillholes within the Phase I mine plan set out in the 2021 Preliminary Economic Assessment ('PEA'). The samples are from the Oxide and Transitional zones and cover the mineralized envelope within the selected drillholes at various acid soluble copper and cyanide soluble copper grade classes. The results of the solubility testwork (bottle roll tests) are outlined in Table-1 and Table-2 below. The copper recovery and final PLS copper grades at the end of the 72-hour leach period show a strong correlation to TCu grade.
Table-1: Copper recovery and PLS grades at the end of the 72-hour leach period.
| Grade Range | Total Copper Rec. (%) | Final PLS (g Cu/l) | ||||
| (TCu%) | Min | Max | Average | Min | Max | Average |
| <0.10 | 8.6 | 74.7 | 38.3 | 0.19 | 0.85 | 0.46 |
| 0.10-0.30 | 14.1 | 87.3 | 51.7 | 0.41 | 2.17 | 1.20 |
| 0.30-0.50 | 25.6 | 94.3 | 66.9 | 2.65 | 3.68 | 2.84 |
| >0.50 | 66.3 | 96.3 | 81.3 | 3.76 | 15.30 | 7.75 |
Table-2: Copper recovery by mineralogical zone and copper species at various grade range.
| Mineral | Grade | Average | Total Cu | ASCu | CNCu |
| Zone | Range (Cu %) | TCu % | Rec % | Rec % | Rec % |
| Oxide | <0.10 | 0.066 | 58.6 | 79.0 | 0 |
| 0.1-0.3 | 0.173 | 50.6 | 73.8 | 13.5 | |
| 0.3-0.5 | 0.386 | 68.6 | 84.7 | 35.7 | |
| 0.5-1.0 | 0.631 | 75.6 | 85.8 | 29.3 | |
| >1.0 | 1.520 | 83.9 | 90.6 | 53.8 | |
| Transitional | <-0.10 | no samples | ns | ns | ns |
| 0.1-0.3 | 0.150 | 41.8 | 70.8 | 11.1 | |
| 0.3-0.5 | 0.443 | 18.7 | 48.7 | 11.7 | |
| 0.5-1.0 | 0.723 | 25.7 | 53.2 | 32.2 | |
| >1.0 | 1.280 | 42.7 | 74.4 | 22.9 |
Notes: TCu=total copper content in sample; PLS=leach solution; g Cu/l= grams of copper contained in 1 liter of leach solution (PLS); ASCu=acid soluble copper; CNCu=cyanide soluble copper.
It is expected that the remainder of the copper contained in the acid soluble copper minerals (malachite, azurite, chrysocolla, cuprite) with additional copper recovery from chalcocite would be recovered over a longer leach period as is typical in ISCR operations.
Geotechnical Program
The development of the Van Dyke copper project contemplates access by way of a decline to a depth of approximately 30-40 meters above the Gila Conglomerate/leach cap contact and advancing an underground ramp in the Gila Conglomerate above the leach cap overlying the Van Dyke deposit. The planned geotechnical program consists of logging of the Gila Conglomerate in six drillholes to collect geomechanical and structural orientation data for ground support analyses and decline and ramp design, identify potential areas of concern and to assist with geotechnical domaining and evaluate ground support requirements. The data to be collected includes Rock quality designation ('RQD'), Fracture frequency, Q` data - joint number ('Jn'), joint roughness ('Jr'), and joint alteration ('Ja'), and Hardness '(ISRM') on broken and whole core. Previously collected acoustic televiewer data ('ATV') from the six drillholes will be reviewed to support the geochemical data.
On completion of the planned testing program, a data gap evaluation will be completed for all available geotechnical and hydrogeological data from the Van Dyke project to determine if additional data is needed to support a PFS level study.
Analytical Procedures
The mineral solubility/mineralogical testwork (QEMSCAN) was completed by Base Met Labs US LTD ('BML') located in Tucson, Arizona and at BML's Kamloops, British Columbia facility. Sample preparation for the mineral solubility (bottle roll) tests consisted of stage crushing 100 percent of the sample to passing 10 mesh (1.70 mm) and split into 1-kilogram test samples. The prepared samples were then subjected to a 72-hour leach period, evaluating copper recovery and acid consumption under the following leaching conditions: 1) 45 % Solids, 2) 1.8 pH (adjusting pH every day to make sure free acid is available for leaching), 3) sampling of the pregnant leach solutions ('PLS') at 2,4,6,8,24,48 and 72 hours, 4) the PLS was analyzed for Cu, Fe, pH, ferrous iron (Fe++) and ferric iron (Fe+++). A 50-gram sample from each leached residue was submitted for Cu, Fe and SeqCu analysis.
A 100-gram sample was separated (riffled out) from each of the 1-kilogram samples and pulverized for QEMSCAN analysis using the BMA (Bulk Mineral Analysis) to provide; 1) Modal Mineralogy and Abundance (including copper speciation), 2) Copper Deportment, and 3) QEMSCAN vs Assay Reconciliation.
Qualified Person
Elmer B. Stewart, MSc. P. Geol., President, and CEO of Copper Fox, is the Company's non-independent, nominated Qualified Person pursuant to National Instrument 43-101, Standards for Disclosure for Mineral Projects, and has reviewed and approves the scientific and technical information disclosed in this news release.
About Copper Fox
Copper Fox is a Tier 1 Canadian resource company focused on copper exploration and development in Canada and the United States. The principal assets of Copper Fox and its wholly owned subsidiaries, being Northern Fox Copper Inc. and Desert Fox Copper Inc., are the
On behalf of the Board of Directors
Elmer B. Stewart
President and Chief Executive Officer
For additional information contact: Jason Shepherd at investor@copperfoxmetals.com or 1-844-464-2820
Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
Cautionary Note Regarding Forward-Looking Information
This news release contains forward-looking statements within the meaning of the Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, and forward-looking information within the meaning of the Canadian securities laws (collectively, "forward-looking information"). Forward-looking information is identifiable by use of the words "believes," "may," "plans," "will," "anticipates," "intends," "budgets," "could," "estimates", "expects", "forecasts", "projects" and similar expressions, and the negative of such expressions. Forward-looking information in this news release include statements about: results from the solubility testwork; a longer leach period recovering the remaining copper; and plans for the geotechnical program on the Gila Conglomerate.
In connection with the forward-looking information contained in this news release, Copper Fox and its subsidiaries have made numerous assumptions regarding, among other things: completing the planned hydrogeologic program on time and within budget; the availability of service providers; the geological, metallurgical, engineering, financial and economic advice that Copper Fox has received is reliable and is based upon practices and methodologies which are consistent with industry standards; and the stability of economic and market conditions. While Copper Fox considers these assumptions to be reasonable, these assumptions are inherently subject to significant uncertainties and contingencies.
Additionally, there are known and unknown risk factors which could cause Copper Fox's actual results, performance, or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking information contained herein. Known risk factors include among others: the copper not recovered within the 72 hour leaching period may not be recovered; the mineralogical tests may not return the desired results or be completed as planned or at all; the geotechnical tests may not be completed as planned or at all; uncertainties relating to interpretation of the previous results; the overall economy may deteriorate; uncertainty as to the availability and terms of future financing; fluctuations in commodity prices and demand; currency exchange rates; and uncertainty as to timely availability of permits and other governmental approvals.
A more complete discussion of the risks and uncertainties facing Copper Fox is disclosed in Copper Fox's continuous disclosure filings with Canadian securities regulatory authorities at www.sedar.com. All forward-looking information herein is qualified in its entirety by this cautionary statement, and Copper Fox disclaims any obligation to revise or update any such forward-looking information or to publicly announce the result of any revisions to any of the forward-looking information contained herein to reflect future results, events, or developments, except as required by law.
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FAQ
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