Positive Initial Metallurgical Results From Stardust Show Copper Recoveries to 98.6% and Gold Recoveries to 93.9%
VANCOUVER, British Columbia, April 19, 2021 (GLOBE NEWSWIRE) — NorthWest Copper Corp. (TSX-V: NWST) (“NorthWest Copper”) is pleased to announce positive results for initial metallurgical test work on its 100% owned Stardust copper-gold project in BC. Combined gravity and flotation produced copper recoveries from 94.2% to 98.6% and gold recoveries from 93.0% to 93.9%. Those tests produced copper in concentrate grades from 21.8% to 26.2%. These strong results further enhance the high-grade Stardust deposit.
Peter Bell, President & CEO of NorthWest Copper states: “These exciting positive results support the advancement of our combined Stardust and Kwanika project. High grades, strong recoveries and a simple flowsheet provide a foundation for the combination. We are finalizing an initial Stardust resource in the next several weeks which will help underpin our unique high-grade copper-gold project.”
Three composites were tested: low, medium, and high grade. Tests were conducted with the high-grade composite including gravity, flotation optimization, rougher kinetics and grind size, then batch cleaner tests. Finally, the low and medium grade composites were tested using parameters from the previous tests. These tests used a primary grind size of 150 microns with a 40 to 50 micron regrind, gravity and flotation. Summary results are shown below.
|Sample||Cu grade||%||Au grade g/t||Cu recovery||Au recovery||Cu grade in concentrate|
|High Grade||3.94||%||4.56 g/t||98.6||%||93||%||26.2||%|
|Medium Grade||2.13||%||2.36 g/t||94.2||%||93.7||%||21.8||%|
|Low Grade||1.11||%||1.30 g/t||94.4||%||93.9||%||22.2||%|
Test work shows copper recovery had limited sensitivity to grind sizes between 75 and 150 microns. Gold showed much higher recoveries at 75 microns vs. 100 or 150 microns but the inclusion of a gravity circuit appears to remove the need for a finer primary grind. The inclusion of the gravity circuit allows for a relatively coarse primary grind size of 150 microns. Gravity recovered between 24% and 42% of the gold in the three tests.
All test work was completed by Base Metallurgical Laboratories Ltd. in Kamloops, BC. Composites received were crushed and split into 2kg test charges. Samples were analyzed prior to testing. A scoping level metallurgical study was undertaken to evaluate the flotation response of three composites prepared to represent a gradient of feed grades. Testing optimized conditions using the high-grade composite; a series of three rougher kinetic flotation tests evaluated the sensitivity of primary grind before optimizing the cleaner circuit with a further five tests. A single cleaner test was performed for each of the low grade and medium grade composites applying established conditions used for the high-grade composite.
The final flowsheet used for testing included gravity concentration of gold by Centrifugal Gold Concentration (CGC) using a laboratory Knelson, followed by cleaning using a Mozley Table at 150 microns. The combined Knelson and Mozley tails were advanced to 10 minutes of rougher flotation, the rougher concentrate was reground to a target of 40 to 50 microns and cleaned, requiring 2 to 3 stages of dilution cleaning.
Technical aspects of this news release have been reviewed, verified and approved by Ian Neill P.Geo., Vice President Exploration of NorthWest Copper, who is a qualified person as defined by NI 43-101.
About NorthWest Copper:
NorthWest Copper is a new diversified copper-gold explorer and developer with an exciting pipeline of projects in British Columbia. With a robust portfolio in a tier one jurisdiction, Northwest Copper is well positioned to participate fully in a strengthening global copper market. Additional information can be found on the Company’s website at www.northwestcopper.ca.
On Behalf of the Board of Directors of NorthWest Copper Corp.
President and Chief Executive Officer
For further information, please contact:
NorthWest Copper Corp.
Email: [email protected]
Neither 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 Statement Regarding Forward Looking Information
All statements, trend analysis and other information contained in this press release about anticipated future events or results constitute forward-looking statements. Forward-looking statements are often, but not always, identified by the use of words such as “seek”, “anticipate”, “believe”, “plan”, “estimate”, “expect” and “intend” and statements that an event or result “may”, “will”, “should”, “could” or “might” occur or be achieved and other similar expressions. All statements, other than statements of historical fact, included herein, are forward-looking statements. Although NorthWest Copper believes that the expectations reflected in such forward-looking statements and/or information are reasonable, undue reliance should not be placed on forward-looking statements since NorthWest Copper can give no assurance that such expectations will prove to be correct. These statements involve known and unknown risks, uncertainties and other factors that may cause actual results or events to differ materially from those anticipated in such forward-looking statements, including the risks, uncertainties and other factors identified in NorthWest Copper’s periodic filings with Canadian securities regulators. Forward-looking statements are subject to business and economic risks and uncertainties and other factors that could cause actual results of operations to differ materially from those contained in the forward-looking statements. Important factors that could cause actual results to differ materially from NorthWest Copper’s expectations include risks associated with the business of NorthWest Copper; risks related to reliance on technical information provided by NorthWest; risks related to exploration and potential development of the Projects; business and economic conditions in the mining industry generally; fluctuations in commodity prices and currency exchange rates; uncertainties relating to interpretation of drill results and the geology, continuity and grade of mineral deposits; the need for cooperation of government agencies and native groups in the exploration and development of properties and the issuance of required permits; the need to obtain additional financing to develop properties and uncertainty as to the availability and terms of future financing; the possibility of delay in exploration or development programs and uncertainty of meeting anticipated program milestones; uncertainty as to timely availability of permits and other governmental approvals; and other risk factors as detailed from time to time and additional risks identified in NorthWest Copper’s filings with Canadian securities regulators on SEDAR in Canada (available at www.sedar.com). Forward-looking statements are based on estimates and opinions of management at the date the statements are made. NorthWest Copper does not undertake any obligation to update forward-looking statements except as required by applicable securities laws. Investors should not place undue reliance on forward-looking statements.