High Recoveries & Product Grades from Unkur Metallurgical Testing
Highlights:
- Sulphide material: recoveries up to 89.1% copper and 82.7% silver using conventional flotation methods producing commercially attractive ~30% copper & ~2,000 g/t silver concentrate
- Oxide material: recoveries up to 96.4% copper with acid leach and 96.7% silver recoveries with cyanide leach
VANCOUVER, August 4, 2020 - Azarga Metals Corp. ("Azarga Metals" or the "Company") (TSX-V:AZR) reports that final results have been received from metallurgical test work on samples taken from the recently completed drilling program on the Unkur Copper-Silver Project in Eastern Russia.
Michael Hopley, President and CEO said: "These final results are very encouraging and show that both copper and silver from the deeper sulphide material and the upper oxide material can be recovered efficiently by conventional methods. Being able to produce a very saleable concentrate consisting of approximately 30% copper and 1,600 - 2,000g/t silver is very positive for the project".
The metallurgical tests were completed by "The Eastern Mining and Metallurgical Research Institute for Non-Ferrous Metals" (VNIITsvetMet). They reported that the chemical analyses of the cupriferous quartz-feldspar sandstone drill core samples sent for metallurgical tests were as follows:
Metal | Oxide | Sulphide |
Copper % | 0.56 | 0.56 |
Silver g/t | 30.8 | 38.0 |
Gold g/t | 0.07 | 0.05 |
These results are positive because they represent close to the anticipated average grades of the Unkur deposit when mined and show no elevated values of deleterious components, such as arsenic, were identified in mineralized material.
Metallurgical Recovery Tests - Sulphide
The best results were from sulphide drill core ground to ±80% -0.071 mm. Using various optimized two-stage cleaning locked cycle standard flotation tests on this material showed 87.8 to 89.1% recovery of copper producing a 25.78% to 30.9% copper concentrate. In this same test, silver showed an 81.6% to 82.7% recovery with concentrate grades ranging from 1633.6 g/t to 2034 g/t - see details in Table 1 below:
Table 1 - Sulphide Test Results
Product | Yield, % | Copper, % | Silver, g/t | Percent Recovery Copper | Percent Recovery Silver |
Concentrate | 1.93 | 25.78 | 1633.6 | 89.1 | 82.7 |
Tailings 1 | 88.10 | 0.053 | 5.7 | 8.4 | 13.2 |
Tailings 2 | 9.97 | 0.14 | 15.6 | 2.5 | 4.1 |
Total Tailings | 98.07 | 0.062 | 6.7 | 10.9 | 17.3 |
Mineralized material | 100.00 | 0.558 | 38.1 | 100.00 | 100.00 |
Product | Yield, % | Copper, % | Silver, g/t | Percent Recovery Copper | Percent Recovery Silver |
Concentrate | 1.59 | 30.9 | 2034 | 87.8 | 81.6 |
Tailings 1 | 87.96 | 0.053 | 6.0 | 8.3 | 13.3 |
Tailings 2 | 10.45 | 0.21 | 19.4 | 3.9 | 5.1 |
Total Tailings | 98.41 | 0.070 | 7.42 | 12.2 | 18.4 |
Mineralized material | 100.00 | 0.56 | 39.65 | 100.00 | 100.00 |
Metallurgical Recovery Tests - Oxide
Tests were run on various size fractions: -20 mm, -10 mm, and -0.071 mm. The best recoveries were achieved by using the finest (-0.071 mm) fraction size. On this material, the best sulphuric acid leach test results achieved were 73.6 to 96.4% recoveries of copper. On the same fraction size, a cyanide leach over a 2-day period showed a 55.6% recovery for copper and a 96.7% for silver - see details in Table 2 below.
Table 2 - Oxide Test Results
Leach Tests | Sulphuric Acid | Cyanide Leach |
Copper recovery | 73.6 - 96.4% | 55.6% |
Silver recovery | Not applicable | 96.7% |
The laboratory work also included a phase analysis of copper minerals identified in the oxide and unoxidized phase of mineralization, which confirms observations of the drill core, summarized as follows:
Copper Minerals | Oxide % | Sulphide% |
Chalcanthite | 12.5 | 3.4 |
Malachite, azurite, chrysocolla, cuprite, tenorite | 83.9 | 0.2 |
Bornite, chalcocite, covellite | 1.8 | 42.8 |
Chalcopyrite | 1.8 | 53.6 |
Totals | 100.0 | 100.0 |
The proportion of acid soluble copper in the oxide material is 96.4%. The proportion of copper sulphides in the sulphide sample is 96.4%.
For the program being reported today, both sulphide material was taken from recent drill holes from deeper parts of the Unkur mineralization. Oxide material was collected from an outcrop.
Qualified Person
Azarga Metals' President and CEO Michael Hopley, a Qualified Person as defined by NI 43-101, verified the data disclosed and has reviewed and approved the disclosure contained in this Press Release.
About Azarga Metals Corp.
Azarga Metals is a mineral exploration and development company that owns 100% of the Unkur Copper-Silver Project in the Zabaikalsky administrative region in eastern Russia. On completion of a first phase physical exploration program in 2016-2018, the Company estimated an Inferred Resource of 62 million tonnes at 0.53% copper and 38.6g/t silver for the project in the report entitled "Technical Report and Preliminary Economic Assessment for the Unkur Copper-Silver Project, Kodar-Udokan, Russian Federation" dated effective 30, August 2018 authored by Tetra Tech Mining & Minerals. The Resource remains open in both directions along strike and down-dip.
"Michael Hopley"
Michael Hopley,
President and Chief Executive Officer
For further information please contact: Doris Meyer, at +1 604 536-2711 ext. 6, visit www.azargametals.com or follow us on Twitter @AzargaMetals. The address of the head office of Azarga Metals is Unit 1 - 15782 Marine Drive, White Rock, BC V4B 1E6, British Columbia, Canada.
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 Statement:
This news release contains forward-looking statements that are based on the Corporation's current expectations and estimates. Forward-looking statements are frequently characterized by words such as "plan", "expect", "project", "intend", "believe", "anticipate", "estimate", "suggest", "indicate" and other similar words or statements that certain events or conditions "may" or "will" occur. Such forward-looking statements involve known and unknown risks, uncertainties and other factors that could cause actual events or results to differ materially from estimated or anticipated events or results implied or expressed in such forward-looking statements. Such factors include, among others: the actual results of current planned exploration activities; conclusions of economic evaluations; changes in project parameters as plans to continue to be refined; possible variations in mineralization grade or recovery rates; accidents, labor disputes and other risks of the mining industry; delays in obtaining governmental approvals or financing; and fluctuations in metal prices. There may be other factors that cause actions, events or results not to be as anticipated, estimated or intended. Any forward-looking statement speaks only as of the date on which it is made and, except as may be required by applicable securities laws, the Company disclaims any intent or obligation to update any forward-looking statement, whether as a result of new information, future events or results or otherwise. Forward-looking statements are not a guarantee of future performance and accordingly undue reliance should not be put on such statements due to the inherent uncertainty therein.
SOURCE: Azarga Metals Corp.
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