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Benchmark Provides Metals Recovery Up to 98% Gold and 97% Silver From Metallurgical Testing at the Lawyers Gold-Silver Project

Press Release

Edmonton – August 13, 2020 – Benchmark Metals Inc. (the “Company” or “Benchmark”) (TSX-V: BNCH) (OTCQB: CYRTF) (WKN: A2JM2X) – is pleased to announce preliminary metallurgical results from composite samples representing three resource target areas. Benchmark’s flagship, 100% owned Lawyers gold-silver project is located in the Golden Horseshoe of north-central British Columbia, Canada.  Three resource areas were tested for preliminary metallurgical response.  These three areas consist of Cliffs Creek North & South (CN & CS), Dukes Ridge (DR), and Amethyst Gold Breccia (AGB) zones.

Combined gravity and leach testing from all three areas have recoveries that range from 91% to 97% gold and 59% to 92% silver. Flotation testing (some with gravity pretreatment) from the three resource areas have recoveries that range from 85% to 98% for gold, and 39% to 97% for silver. The metal recovery rate, or also known as the mineral recovery percentage, indicates what percentage of gold and silver are expected to be recovered after the extractive process has taken place. The test work is an indication of future mineral processing plant performance based on the extraction process.

John Williamson, CEO, commented, “The metallurgy results have provided exceptional recovery for both gold and silver using conventional technology. This is a major engineering milestone to rapidly advance the Project through project development towards a production decision. Ongoing metallurgy, drilling, baseline studies, engineering and permitting are all supportive endeavors for a near-term Preliminary Economic Assessment (PEA). The strong, gold and silver recovery rates will contribute to the economics of this Project.”

Summary

  • Initial metallurgical test work results support the advancement of the Lawyers Gold-Silver Project
  • Additional metallurgical testing is planned to improve, optimize and better define the process flowsheet with ongoing project development into a Preliminary Economic Study (PEA) scheduled for Q1/Q2 2021
  • Overall recovery grades of gold and silver continue to be promising for all target resource zones tested
  • Gold and silver recoveries for mineralized material are excellent with conventional processing technology

F. Wright Consulting Inc. is engaged to evaluate and complete preliminary metallurgical analysis for the Lawyers Gold-Silver Project. Analytical and related test work was performed at Bureau Veritas Minerals (BVM) Metallurgical Division, an accredited facility located in Vancouver, Canada. The initial work has been performed on three composite samples consisting of a Cliff Creek North (CN) and Cliff Creek South (CS) based on five drill holes and representing the major bulk tonnage resource target for the project.  Also tested was a drill hole interval composite from Dukes Ridge (DR3 98-172) and two Amethyst Gold Breccia Zone (AGB) drill hole interval composites (AB4 160-214 & AB1 210-236).

Initial results indicate that whole ore leaching can expect an average recovery in mid-ninety percent range for gold.  Silver recovery is more variable ranging from 59% to 93% depending on the sample and leach conditions used.  The principal resource target of Cliff Creek North had the highest silver leach recoveries ranging from 83% to 93%.  Leach reagent consumption was shown to be good, with generally less than 0.7 kg/t lime Ca(OH2) under planned process conditions to maintain a protective slurry alkalinity of pH ~10.5. Consumption of sodium cyanide was ~ 2.6 g/t or less in all samples.  Based on initial results whole ore leaching offers the most promising treatment option for the Lawyers Project.  A summary of selected tests on the intervals tested is presented in Table 1.  Typical conditions used retention times of 32 to 48 hours and at a moderate grind of product particle size 80% passing (P80) 74 to 106 microns.  Higher grade intervals benefit from the longer leach retention and finer P80.

Table 1: – Leach Recovery Summaries

Sample ID Calc Hd (g/t) Tail (g/t) Recovery (%)
Drill Hole # (m) Au Ag Au Ag Au Ag
Cliff Creek (5 drill hole intervals)
CN3 176-195 2.13 86.6 0.11 15 94.7 82.6
CN6 72-125 0.73 38.4 0.07 6 90.5 84.4
CN5 113-179 0.60 51.6 0.04 4 93.4 92.2
CS10 228-330 0.89 14.4 0.05 4 94.7 77.1
CN25 127-150 3.04 132 0.06 9 97.8 93.2
Amethyst Gold Breccia Zone (2 drill hole intervals)
AB1 210-236 2.48 165 0.09 32 96.2 80.6
AB4 160-214 1.35 44.1 0.03 18 98.0 59.2
Dukes Ridge (one drill hole interval)
DR3 98-172 1.11 34.7 0.06 5 94.3 85.6

Open cycle froth flotation response is also encouraging for the samples tested for the Cliff Creek Zone.  This was supported by an initial locked cycle test.  The preliminary flowsheet indicates that a moderate primary grind of approximately P80 74 microns is typically sufficient. Xanthate is used as a collector and bulk concentrate can be cleaned in two stages without the need for regrind.  Dukes Ridge and AGB samples have lower sulphide content and indicated lower more variable precious metal recoveries, although future testing may improve on this. Higher grade samples should include gravity pretreatment and may require finer primary grinding with regrinding of a rougher concentrate prior to cleaning.  In all cases the samples tested show an impressive mass upgrade along with final precious metals content.  A summary of the float responses to date are provided in Table 2.

Image 1: Drilling at the Cliff Creek Zone

Table 2: – Flotation Response Summaries

Sample ID Calc Hd (g/t) 2nd Cl. Conc. Tail (g/t) Bulk Rec. (%)
Drill Hole # (m) Au Ag Wt.% Au, g/t Ag, g/t Au Ag Au Ag
Cliff Creek (5 drill hole intervals)
CN3 176-195 2.31 90.1 4.2 46.9 1839 0.10 8.8 96.6 91.9
CN6 72-125 0.77 40.9 2.4 25.3 1311 0.07 5.0 92.2 89.6
CN5 113-179 0.58 51.8 4.9 11.5 992 0.01 1.7 98.9 97.2
CS10 228-330 1.03 17.6 2.2 41.1 677 0.04 2.3 96.3 88.6
CN25 127-150 testing in progress
Amethyst Gold Breccia Zone (2 drill hole
intervals)
AB1 210-236 2.53 168 0.42 335 21050 0.44 53 85.6 73.7
AB4 160-214 0.97 42 0.23 239 3485 0.17 31 85.4 38.9
Dukes Ridge (one drill hole interval)
DR3 98-172 1.07 37.4 1.4 30.6 1862 0.16 8.0 86.9 81.6

The technical content of this news release has been reviewed and approved by Frank Wright, P.Eng., independent metallurgical consultant a qualified person as defined by National Instrument 43-101.

About Benchmark Metals
Benchmark Metals Inc. is a Canadian mineral exploration company focused on proving and developing the substantial resource potential of the Lawyer’s Gold-Silver Project, located in the prolific Golden Horseshoe of northern British Columbia, Canada.  The Company trades on the TSX Venture Exchange in Canada, the OTCQB Venture Market in the United States, and the Tradegate Exchange in Europe.  Benchmark is managed by proven resource sector professionals, who have a track record of advancing exploration projects from grassroots scenarios through to production.

ON BEHALF OF THE BOARD OF DIRECTORS

s/ “John Williamson”
John Williamson, Chief Executive Officer

For further information, please contact:
Jim Greig
Email: [email protected]
Telephone: +1 604 260 6977

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