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Discovery Silver Corp TSX Venture: DSV-X

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Discovery Reports Excellent Recoveries from Metallurgical Test Work on Cordero

GlobeNewswire - Tue Sep 7, 6:00AM CDT

Discovery Silver Corp. (TSX-V: DSV, OTCQX: DSVSF) ("Discovery" or the "Company") is pleased to announce results from its metallurgical test program on representative samples from the Cordero deposit. This program represents the most comprehensive test work completed on Cordero to date. Tests were completed at the Blue Coast Research Ltd. ("Blue Coast") laboratory located in Parksville, BC, Canada. Highlights from the test work include:

Sulphide flotation test work

Oxide & transition cyanidation test work

Taj Singh, President and CEO, states: "The results from this metallurgical test work program represent a major de-risking step for Cordero. All major rock types hosting sulphide ore returned excellent recoveries via conventional flotation processes to generate clean, highly saleable concentrates.

In addition, there were two new positive developments that also emerged from the test work. Firstly, the highest recoveries were achieved at coarse grind sizes of 175-200 microns, which should help reduce capital and operating costs for the project. Secondly, mineralized oxide and mixed oxide-sulphide (transition) "pre-strip" material that sits at surface above the large sulphide ore body responded very well to cyanidation introducing the potential to heap leach this material at the start of the mine life. Both developments should have a positive impact on the overall project economics that will be outlined in our PEA due for release next quarter."


Differential lead-zinc flotation test work was completed on medium-grade sulphide samples representing the four different rock types at Cordero. Samples were sourced from across the deposit in both the North and South Corridor. Test work confirmed excellent recoveries for silver, lead and zinc via conventional flotation processes to generate separate lead and zinc concentrates. Saleable concentrate grades were achieved and levels of penalty elements for both concentrates were insignificant. Significantly, close to 90% of the recovered silver reports to the lead concentrate where the highest payabilities are applicable.

Test  Rock Type             Head Grade                  Lead + Zinc Circuit
                                                        Recovery to Concentrate
                            Ag    Au    Pb   Zn   AgEq  Ag    Au    Pb    Zn
                            (g/t) (g/t) (%)  (%)  (g/t) (%)   (%)   (%)   (%)
LCT-1 Breccia - Volcanic    35    0.23  0.55 0.83 108   89    19    91    90
LCT-2 Breccia - Sedimentary 37    0.21  0.46 0.55 93    84    16    89    86
LCT-3 Volcanic              34    0.11  0.43 0.67 86    83    19    85    81
LCT-4 Sedimentary           27    0.12  0.43 0.73 82    80    18    83    89

Sample selection:


Locked cycle tests:

Test  Lead Circuit                        Zinc Circuit
      Recovery to Conc. Concentrate Grade Recovery to Conc. Concentrate Grade
      Ag    Au    Pb    Ag    Au    Pb    Ag    Au    Zn    Ag    Au    Zn
      (%)   (%)   (%)   (g/t) (g/t) (%)   (%)   (%)   (%)   (g/t) (g/t) (%)
LCT-1 79    13    91    2,923 3.1   53.0  11    7     90    237   1.0   46.3
LCT-2 75    12    89    3,774 3.4   55.7  9     4     86    397   0.9   54.6
LCT-3 70    13    85    3,318 1.9   50.1  13    6     81    400   0.7   50.9
LCT-4 70    13    83    2,886 2.3   54.0  10    5     89    213   0.4   51.4

Concentrate analysis:

Element Average Grade Penalty Threshold
Lead Concentrate:
As      0.38%         0.50%
Sb      0.54%         0.50%
Hg      11 ppm        100 ppm
F       50 ppm        500 ppm
Zinc Concentrate:
As      0.21%         0.30%
Fe      8.87%         8.00%
Cd      0.48%         0.30%
SiO2    1.32%         3.50%
Hg      15 ppm        100 ppm
F+Cl    300 ppm       500 ppm
Se      22 ppm        300 ppm
Mn      0.91%         0.50%

Average grade was calculated as an arithmetic average of the concentrates from the four locked cycle tests

Penalty thresholds vary between smelters; the thresholds listed above are representative of common thresholds typically applied on lead and zinc concentrates

Planned additional test work:


Cyanidation test work was completed on the oxide and mixed oxide-sulphide ("transition") material at Cordero. The oxide and transition material in aggregate represents approximately 5-10% of the total ore body. Test work consisted of coarse bottle roll test work at different crush / grind sizes. Based on the excellent results from these initial tests, column leach test work commenced in July 2021 with McClelland Laboratories, Inc. ("McClelland") based in Reno, Nevada. This will be the first column leach test work conducted on oxide and transition material and if successful, it offers the potential that a commercial heap leach operation could be included in the processing plan in the early years of the project life. Such a heap leach operation would recover silver and gold from "pre-strip" material that would typically be regarded as waste rock. Preliminary results from the column leach test work are expected to be received in 4Q 2021, in time to be included in the upcoming PEA.

Coarse Bottle Roll tests:

Crush / Grind Size    Material   Head Grade  Recoveries
                                 Ag    Au    Ag    Au
                                 (g/t) (g/t) (%)   (%)
0.15 mm (150 microns) Oxide      44    0.07  80    63
0.30 mm (300 microns) Oxide      44    0.07  77    62
3.4 mm (1/8 in)       Oxide      44    0.07  65    61
6.7 mm (1/4 in)       Oxide      58    0.10  59    71
12.7 mm (1/2 in)      Oxide      44    0.07  54    61
6.7 mm (1/4 in)       Transition 52    0.07  63    75
12.7 mm (1/2 in)      Transition 52    0.07  54    72

All crush and grind size test work was completed by Blue Coast at a target NaCN dosage of 1.0 g/L except for the 1/4 inch oxide sample which was completed by McClelland at NaCN dosages of 1.0 g/L and 2.0 g/L (the average of these two test results is shown in the table)

Planned test work

About Discovery

Discovery's flagship project is its 100%-owned Cordero project, one of the few silver projects globally that offers margin, size and scaleability. Cordero is located close to infrastructure in a prolific mining belt in Chihuahua State, Mexico, and is supported by an industry leading balance sheet with over C$80 million available for aggressive exploration, resource expansion and future development. Discovery was a recipient of the 2020 TSX Venture 50 award and the 2021 OTCQX Best 50 award.

On Behalf of the Board of Directors,

Taj Singh, M.Eng, P.Eng, CPA,

President, Chief Executive Officer and Director

For further information contact:

Forbes Gemmell, CFA

VP Corporate Development & Investor Relations

Phone: 416-613-9410



Qualified Person

The scientific and technical content of this press release was reviewed and approved by Tommaso Roberto Raponi, P.Eng. who is a "Qualified Person" as defined by National Instrument 43-101 - Standards of Disclosure for Mineral Projects ("NI 43-101"). Data verification consisted of ensuring that the samples selected came from within the area where the Mineral Resource was estimated. The QP checked that the sampling protocol used was applicable for the planned test work. In the QP's opinion, the test work conducted was completed by a reputable metallurgical testing facility and used industry-standard methods. Mr. Raponi is a consultant to Ausenco Engineering Canada Inc. ("Ausenco") and is considered to be "independent" of Discovery for purposes of section 1.5 of NI 43-101.

About Ausenco

Ausenco is a global diversified engineering, construction and project management company providing consulting, project delivery and asset management solutions to the resources, energy and infrastructure sectors. Ausenco's experience in gold projects ranges from conceptual, pre-feasibility and feasibility studies for new project developments to project execution with EPCM and EPC delivery.

About Blue Coast

Blue Coast, founded in 2009, owns and operates a 12,000 square-foot laboratory in Parksville, BC, Canada, and has a team of minerals engineers, scientists and technicians with experience that spans decades. Blue Coast provides high-quality metallurgical testing, analytical services, flowsheet development, consulting and operational support and are a well-known and trusted partner in the global minerals industry.


The most recent technical report for the Cordero Project is the 2018 Preliminary Economic Assessment (PEA) authored by M3 Engineering and Technology Corp and includes the most recent resource estimate, completed by Independent Mining Consultants, Inc. It is available on Discovery's website and on SEDAR under Levon Resources Ltd, a wholly owned subsidiary of Discovery.

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

This news release is not for distribution to United States newswire services or for dissemination in the United States.

This news release does not constitute an offer to sell or a solicitation of an offer to buy nor shall there be any sale of any of the securities in any jurisdiction in which such offer, solicitation or sale would be unlawful, including any of the securities in the United States of America. The securities have not been and will not be registered under the United States Securities Act of 1933, as amended (the "1933 Act") or any state securities laws and may not be offered or sold within the United States or to, or for account or benefit of, U.S. Persons (as defined in Regulation S under the 1933 Act) unless registered under the 1933 Act and applicable state securities laws, or an exemption from such registration requirements is available.

Cautionary Note Regarding Forward-Looking Statements

This news release may include forward-looking statements that are subject to inherent risks and uncertainties. All statements within this news release, other than statements of historical fact, are to be considered forward looking. Although Discovery believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results or developments may differ materially from those described in forward-looking statements. Factors that could cause actual results to differ materially from those described in forward-looking statements include fluctuations in market prices, including metal prices, continued availability of capital and financing, and general economic, market or business conditions. There can be no assurances that such statements will prove accurate and, therefore, readers are advised to rely on their own evaluation of such uncertainties. There can be no assurance that the Private Placement will close on the announced terms. Discovery does not assume any obligation to update any forward-looking statements except as required under applicable laws.

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