Western Exploration Inc. (TSXV: WEX; OTCQX: WEXPF) (the "Company" or "Western Exploration") is pleased to announce the results of 2024 metallurgical testing on composite samples from the Jarbidge rhyolite hanging wall zone of the Gravel Creek deposit.
Highlights from the work include:
Western Exploration CEO, Darcy Marud said, "Preliminary metallurgical test work on Gravel Creek hanging wall mineralization has returned very positive results for the recovery of gold and silver to concentrate. The recoveries are similar to past Gravel Creek metallurgical test work and demonstrate a potential path to economic recovery for precious metals."
2024 Flotation Metallurgy Sample Locations
Flotation test work was conducted on a gold and silver bearing diamond drill composite from core holes WG456 and WG457, drilled in 2023 in the Jarbidge rhyolite. The two oriented core holes were completed to evaluate resource expansion potential in mineralized vein/breccia trends northeast of the Gravel Creek resource (Figure 1).
Flotation Program and Results
All test work was completed by McClelland Laboratories, Inc ("MLI") of Sparks, Nevada. Flotation testing was conducted on a gold and silver bearing Gravel Creek drill core composite, designated 4991-001, to evaluate response to flotation processing. The composite comprised sulphidic mineralization ranging from 316 meters to 731 meters downhole depths from two drill holes (WG456 and WG457).
Composite assays showed that it contained 6.14 g/t Au, 206 g/t Ag and 2.71% sulphide sulphur. Cyanide shake analysis showed that the sample had cyanide soluble to fire assay ratios (CN/FA) of 53.4% for gold and 36.8% for silver. The composite contained negligible amounts (<0.1%) carbon. A preg-rob assay showed that it was not preg-robbing.
Initially, six rougher flotation tests were conducted at feed sizes ranging from 80%-150 micron to 80%-45 micron. A typical bulk sulphide flotation collector reagent suite was employed for all tests. Following grind optimization testing, a bulk rougher concentrate was produced and used for preliminary cleaner flotation testing. The objectives for the testing were to maximize gold and silver recovery and concentrate grades. Sulphide sulphur recoveries were also tracked during testing. Variability in flotation tail grade caused significant variability in flotation gold recoveries.
Flotation testing showed that the Gravel Creek mineralization responded very well to bulk sulphide flotation treatment. Gold and silver recoveries of as high as >92% were achieved with rougher flotation mass pulls of approximately 11%, Table 1 and Figure 2.
Table 1. - Flotation Concentration Test Results, Test F-5, Gravel Creek Composite 4991-001, 80%-75-micron Feed Size |
||||||||||||||||||||||
Wt. |
Cum. Wt. |
Assay |
Au Distribution |
Ag Distribution |
S= Distribution |
|||||||||||||||||
Product |
% |
% |
Au g/t |
Ag g/t |
% S= |
% |
Cum. % |
% |
Cum. % |
% |
Cum. % |
|||||||||||
Ro. Conc. Stg. 1 (0-2 min) |
4.1 |
4.1 |
95.5 |
3,360 |
28.07 |
57.0 |
57.0 |
64.0 |
64.0 |
42.9 |
42.9 |
|||||||||||
Ro. Conc. Stg. 1 (2-5 min) |
2.3 |
6.4 |
54.1 |
1,480 |
28.96 |
18.1 |
75.1 |
15.8 |
79.8 |
24.8 |
67.7 |
|||||||||||
Ro. Conc. Stg. 2 |
2.3 |
8.7 |
47.4 |
1,010 |
22.17 |
15.8 |
90.9 |
10.8 |
90.6 |
19.0 |
86.7 |
|||||||||||
Ro. Conc. Stg. 3 |
0.9 |
9.6 |
22.2 |
546 |
12.73 |
2.9 |
93.8 |
2.3 |
92.9 |
4.3 |
91.0 |
|||||||||||
Ro. Conc. Stg. 4 |
0.6 |
10.2 |
12.4 |
306 |
7.42 |
1.1 |
94.9 |
0.9 |
93.8 |
1.7 |
92.7 |
|||||||||||
Ro. Conc. Stg. 5 |
0.4 |
10.6 |
7.0 |
206 |
3.81* |
0.4 |
95.3 |
0.4 |
94.2 |
0.6 |
93.3 |
|||||||||||
Ro. Tail |
89.4 |
100.0 |
0.36 |
14 |
0.20 |
4.7 |
100.0 |
5.8 |
100.0 |
6.7 |
100.0 |
|||||||||||
Composite |
100.0 |
|
6.87 |
215 |
2.68 |
100.0 |
|
100.0 |
|
100.0 |
|
|||||||||||
* Insufficient sample was available for sulphide assay. The average of the adjacent product grades was used. |
Preliminary cleaner flotation testing showed that it was possible to significantly increase concentrate grades by cleaning. Cleaner concentrate grades of as high as >70 g/t Au, >3,900 g/t Ag and 41% sulphide sulphur were achieved.
Regrinding the rougher concentrate for as much as 90 minutes resulted in production of a cleaner concentrate that was 3.2% of the ore weight, assayed 72.4 g/t Au, 3,920 g/t Ag and 41.07% sulphide sulphur and represented recoveries of 35.9% gold, 59.6% silver and 49.2% sulphide sulphur. The corresponding cleaner tail was another 7.4% of the feed weight, assayed 40.6 g/t Au, 898 g/t Ag and 16.04% sulphide sulphur and represented additional recoveries of 46.5% gold, 31.5% silver and 44.4% sulphide sulphur, Table 2.
Table 2. - Rougher/Cleaner Flotation Concentration Test Results, Gravel Creek Composite 4991-001, 4991 F-6 Rougher Concentrate, 90 min Regrind of Ro. Conc. |
||||||||||||||||||||||
|
Wt. |
|
Cum. Wt. |
|
Assay |
|
Au Distribution |
|
Ag Distribution |
|
S= Distribution |
|||||||||||
Product |
% |
|
% |
|
Au g/t |
|
Ag g/t |
|
% S= |
|
% |
|
Cum. % |
|
% |
|
Cum. % |
|
% |
|
Cum. % |
|
Cl. Conc. |
3.2 |
|
3.2 |
|
72.4 |
|
3,920 |
|
41.07 |
|
35.9 |
|
35.9 |
|
59.6 |
|
59.6 |
|
49.2 |
|
49.2 |
|
Cl. Tail |
7.4 |
|
10.6 |
|
40.6 |
|
898 |
|
16.04 |
|
46.5 |
|
82.4 |
|
31.5 |
|
91.1 |
|
44.4 |
|
93.6 |
|
Ro. Tail |
89.4 |
|
100.0 |
|
1.27 |
|
21 |
|
0.19 |
|
17.6 |
|
100.0 |
|
8.9 |
|
100.0 |
|
6.4 |
|
100.0 |
|
Composite |
100.0 |
|
|
|
6.46 |
|
211 |
|
2.67 |
|
100.0 |
|
|
|
100.0 |
|
|
|
100.0 |
|
|
A gravity concentration test was conducted on tailings from one of the flotation tests to evaluate causes for variability in flotation tail grade. Results showed that most (77%) of the gold contained in the flotation rougher tail sample was gravity recoverable. The gravity concentrate produced was 0.07% of the flotation tail weight, assayed 2,250 g/t Au and represented 77.0% of the gold contained in the flotation tailing.
Follow up locked-cycle flotation test work was conducted at an 80%-150 micron grind size on gravity tails generated from the sample composite. Test results showed that the combined gravity and flotation concentrate was 10.9% of the feed weight, assayed 57.1 g/t Au and 1,725 g/t Ag. Recoveries reporting to this combined concentrate were 94.8% gold and 89.8% silver of the values contained in the whole feed. The combined concentrate described above included a gravity cleaner concentrate and flotation rougher concentrate (from locked-cycle testing on the gravity tailing). The gravity concentrate was 0.16% of the feed weight, assayed 920 g/t Au and 5,750 g/t Ag and represented gold and silver recoveries of 22.4% and 4.4% respectively. The gravity concentrate was not assayed for sulphide sulphur. The flotation concentrate was 10.74% of the whole feed weight, assayed 44.3 g/t Au, 1,665 g/t Ag and 21.9% sulphide sulphur and represented gold and silver recoveries of 72.4% and 85.4% respectively of values contained in the whole feed weight.
Table 3. ? Gravity/Flotation Test, Gravel Creek Composite 4991-001, 80%-212-micron (Gravity Test G-2)/80%-150 micron Regrind (Locked Cycle Flotation Test F-9, average of Cycles 5&6) |
||||||||||||||||||||||
Wt. |
Cum. Wt. |
Assay |
Au Distribution |
Ag Distribution |
S= Distribution |
|||||||||||||||||
Product |
% |
% |
Au g/t |
Ag g/t |
% S= |
% |
Cum. % |
% |
Cum. % |
% |
Cum. % |
|||||||||||
Grav. Cl. Conc. |
0.16 |
0.16 |
920 |
5750 |
N/A* |
22.4 |
22.4 |
4.4 |
4.4 |
N/A |
N/A |
|||||||||||
Flotation Ro. Conc. |
10.74 |
10.90 |
44.3 |
1665 |
21.9 |
72.4 |
94.8 |
85.4 |
89.8 |
95.3 |
95.3 |
|||||||||||
Flotation Ro. Tail |
89.10 |
100.00 |
0.38 |
24 |
0.13 |
5.2 |
100.0 |
10.2 |
100.0 |
4.7 |
100.0 |
|||||||||||
Composite |
100.00 |
|
6.56 |
209 |
2.46 |
100.0 |
|
100.0 |
|
100.0 |
|
|||||||||||
*N/A denotes Not Available |
About the Aura Project
The 6,000-hectare Aura Project has established mineral resource estimates in three different deposits (Doby George, Gravel Creek and Wood Gulch), as reported in the "2021 Updated Resource Estimates and Technical Report for the Aura Gold-Silver Project, Elko County, Nevada" dated October 20, 2021 (with an effective date of October 14, 2021) that was prepared for the Company by Mine Development Associates (the "Technical Report"; see Table 4 below). The mineral resource estimates in the Technical Report were established in accordance with National Instrument 43-101 ? Standards of Disclosure for Mineral Projects ("NI 43-101").
In addition, the Aura Project has well established infrastructure including year-round accessibility by highway and county-maintained road and nearby access to water and electricity. Western Exploration has exploration, development, and mining rights on 930 hectares of privately owned land through a mineral lease agreement with a local landowner and may purchase those fee lands at any time for the development of Doby George.
Table 4. Mineral resource estimates for the Aura Project as reported in the 2021 Technical Report. |
||||||||||||||
MINERAL RESOURCE(1) |
||||||||||||||
|
Indicated |
Inferred |
||||||||||||
|
Tonnes |
Au
|
Au
|
Ag
|
Ag
|
AuEq
|
AuEq
|
Tonnes |
Au
|
Au
|
Ag
|
Ag
|
AuEq
|
AuEq
|
Doby George(2) |
12,922,000 |
0.98 |
407,000 |
- |
- |
0.98 |
407,000 |
4,999,000 |
0.73 |
118,000 |
- |
- |
0.73 |
118,000 |
Wood Gulch(3) |
- |
- |
- |
- |
- |
- |
- |
4,359,000 |
0.66 |
93,000 |
5.80 |
808,000 |
0.74 |
104,543 |
Gravel Creek(4) |
1,315,000 |
4.73 |
200,000 |
75.0 |
3,169,000 |
5.81 |
245,271 |
2,744,000 |
4.16 |
367,000 |
60.20 |
5,307,000 |
5.02 |
442,814 |
TOTAL |
14,237,000 |
1.33 |
607,000 |
75.0 |
3,169,000 |
1.43 |
652,271 |
12,102,000 |
1.48 |
578,000 |
15.74 |
6,115,000 |
1.71 |
665,357 |
Notes: | ||
(1) |
Au equivalent oz assumes US$1,800 per oz Au and 70:1 ratio of Ag:Au. |
|
(2) |
Pit constrained 0.2 g/t AuEq cutoff for oxide, 0.4 g/t Au cutoff for mixed and 1.4 g/t Au cutoff for unoxidized. |
|
(3) |
Pit constrained 0.2 g/t AuEq cutoff. |
|
(4) |
3.0 g/t Au cutoff. |
|
See "Cautionary Statements Regarding Estimates of Mineral Resources" below. |
About Western Exploration
Western Exploration is focused on advancing the 100% owned gold-silver Aura project, located approximately 120 kilometers/75 miles north of the city of Elko, Nevada. The project includes three unique gold and silver deposits: Doby George, Gravel Creek, and Wood Gulch.
Western Exploration is comprised of an experienced team of precious metals experts that aim to lead the company to becoming North America's premier gold and silver development company.
Additional information regarding Western Exploration and the Aura Project can be found on the Company's website and on SEDAR+ (www.sedarplus.ca) under the Company's issuer profile.
Qualified Person Approval
The scientific and technical information in this news release has been reviewed and approved by Mark Hawksworth, General Manager of the Aura Project, and Jack McPartland of MLI, each of whom is a "qualified person" within the meaning of NI 43-101.
Quality Assurance / Quality Control
Exploration program design, Quality Assurance/Quality Control ("QA/QC") and the interpretation of results is performed by qualified persons employing a QA/QC program consistent with NI 43-101 and industry best practices. For Western Exploration legacy samples, standards and blanks and duplicates were generally included approximately every 20th sample for QA/QC purposes by the Company as well as the lab. Approximately 5% of sample pulps are sent to secondary laboratories for check assay. QA/QC controls are not fully documented for legacy assays from the 1980s and 1990s but Mine Development Associates conducted rigorous evaluation of adjacent assay intervals as part of the Technical Report resource calculations. Please see below under the heading "Cautionary Note Regarding Forward-Looking Information" for further details regarding the risks facing Western Exploration.
Metallurgical Test Work
Interval Preparation and Assay: A total of 28 drill interval samples, from the Gravel Creek deposit were received on January 18, 2024. Select samples from drill holes WG456 (ranging from 1,792.7' to 2,397') and WG457 (ranging from 1,036.5' to 2,319.2') were used for testing. The interval samples were previously crushed to a nominal 2mm and weighed 0.3 to 7.3 kg each. Select samples (19) were combined in entirety to produce Gravel Creek composite 4991-001.
The entire composite was stage crushed to just passing 1.7mm in size. The -1.7mm composite was thoroughly blended and split to obtain multiple 1.0 kg samples for testing and triplicate 0.25 kg samples for head assay.
The composite was assayed directly in triplicate, using conventional fire assay fusion procedures, to determine gold and silver content. A single cyanide shake analysis was conducted, with and without a "gold spike" leach solution (preg-rob test series). Carbon and sulphur speciation analyses were conducted using Leco/pyrolysis methods. A single multi-element ICP scan was conducted.
Flotation Testing
A total of six rougher flotation tests were conducted on composite 4991-001, at feed sizes ranging from 80%-150µm to 80%-45µm, to evaluate response to flotation and to optimize flotation feed size. The tests were conducted using a bulk sulphide flotation reagent scheme, designed to maximize recoveries of sulphide minerals, gold and silver.
Initially, a scouter rougher flotation test was conducted on a 1 kg sample at an 80%-75µm feed size, to obtain preliminary information concerning response of the ore to flotation treatment. Based on those results, a series of three additional rougher flotation tests (1 kg each) were conducted at feed sizes of 80%-150µm, 80%-106µm and 80%-45µm to optimize feed size. Based on those test results, the 75µm feed size was selected for further testing. A kinetic rougher flotation test was conducted at the 75µm feed size, to establish the relationships between flotation time, mass pull, rougher concentrate grade and recovery. A bulk flotation test (16 kg) was conducted at the 75µm feed size to generate rougher concentrate for cleaner flotation testing. Cleaner flotation tests (3) were conducted on the resulting bulk rougher concentrate to evaluate the potential for increasing concentrate grade by regrinding and cleaner flotation.
The same reagent suite was used for all rougher flotation tests. Flotation was conducted using a Denver laboratory scale flotation unit at 1,200 rpm. Each ground pulp was slurried with grind water to achieve 33% solids (wt/wt) and was conditioned for 5 minutes with 0.25 kg/mt CuSO4?5H2O.
Flotation was conducted in 5 stages with incremental additions of 0.005 kg/mt ore of PAX (potassium amyl xanthate) and 0.010 kg/mt AERO 208 (dithiophosphate) collectors at each stage. Respective total addition of each reagent was 0.025 and 0.050 kg/mt ore. AEROFROTH 65 was used as frother. The pulp was floated at natural pH. For all rougher flotation tests, except for the kinetic test, the 5 stages of concentrate were combined into a rougher concentrate. Those rougher concentrates were dried, weighed and assayed directly to determine gold, silver and sulphide sulphur content.
The five staged rougher concentrate samples generated from the kinetic flotation test (F-5) were each dried, weighed and assayed separately for the same constituents.
In the case of the bulk (16 kg) rougher flotation test (F-6), rougher flotation was conducted in two 8 kg lots, using a larger flotation machine. The rougher concentrates produced from those two tests were combined, dried, weighed and split to obtain three 0.5 kg samples for cleaner flotation testing and 0.2 kg for assay. The combined rougher concentrate was assayed directly to determine gold, silver and sulphide sulphur content. The rougher tails from each 8 kg lot were dried, weighed and assayed separately, in triplicate to determine gold silver and sulphide sulphur content (one sulphide sulphur assay per 8 kg lot). Results presented for rougher flotation test F-6 are based on the average of assay results from the two 8 kg lots (designated F-6A and F-6B).
Cleaner flotation tests (3) were conducted on the rougher concentrate generated from the bulk flotation test (F-6). The tests were conducted on 0.5 kg splits of rougher concentrate after regrinds of 1 minute (polish grind), 45 minutes and 90 minutes. Cleaner flotation was conducted without additional collector or promoter. Frother was added as required. The resulting cleaner concentrates and cleaner tails were dried, weighed and assayed to determine gold, silver and sulphide sulphur content.
For additional information on the Aura Project, please see the Technical Report, which has been prepared in accordance with the requirements of NI 43-101, a copy of which is available on SEDAR+ (www.sedarplus.ca) under Western Exploration's issuer profile and on Western Exploration's corporate website (www.westernexploration.com).
Cautionary Statements Regarding Estimates of Mineral Resources
This news release uses the terms measured mineral resources, indicated mineral resources, and inferred mineral resources as a relative measure of the level of confidence in the resource estimate. Readers are cautioned that mineral resources are not mineral reserves and that the economic viability of mineral resources that are not mineral reserves has not been demonstrated. The mineral resource estimate disclosed in this news release may be materially affected by geology, environmental, permitting, legal, title, socio-political, marketing, or other relevant issues. It cannot be assumed that all or any part of the inferred mineral resources will ever be upgraded to the category of indicated mineral resource or measured mineral resource. The mineral resource estimate is classified in accordance with the Canadian Institute of Mining, Metallurgy and Petroleum's "CIM Definition Standards on Mineral Resources and Mineral Reserves" (CIM) incorporated by reference into NI 43-101. Under NI 43-101, estimates of inferred mineral resources may not form the basis of feasibility or pre-feasibility studies or economic studies except for preliminary economic assessments. Readers are cautioned not to assume that further work on the stated resources will lead to mineral reserves that can be mined economically.
Inferred mineral resources have a great amount of uncertainty as to their existence and as to whether they can be mined legally or economically. On October 31, 2018, the U.S. Securities and Exchange Commission adopted new mining disclosure rules ("S-K 1300") that are more closely aligned with current industry and global regulatory practices and standards, including NI 43-101, although there are some differences in the two standards. Accordingly, information concerning mineral deposits contained in this release may not be comparable with information made public by U.S. companies that report in accordance with S-K 1300.
Cautionary Note Regarding Forward-Looking Information
This news release may contain "forward-looking information" and "forward-looking statements" within the meaning of the applicable Canadian and United States securities legislation (collectively, "forward-looking statements"). These forward-looking statements, by their nature, require the Company to make certain assumptions and involve known and unknown risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such forward-looking statements. Any statement that involves predictions, expectations, interpretations, beliefs, plans, projections, objectives, assumptions, future events or performance (often, but not always, using phrases such as "expects", or "does not expect", "is expected", "interpreted", "management's view", "anticipates" or "does not anticipate", "plans", "budget", "scheduled", "forecasts", "estimates", "potential", "feasibility", "believes" or "intends" or variations of such words and phrases or stating that certain actions, events or results "may" or "could", "would", "might" or "will" be taken to occur or be achieved) are not statements of historical fact and may be forward-looking information and are intended to identify forward-looking information. This news release contains the forward-looking information pertaining to, among other things: the focus and results of the surface exploration program; the accuracy of results from prior exploration activities conducted at the Aura Project; the key assumptions, parameters and methods used to estimate the mineral resource estimate disclosed in this news release; the prospects, if any, of the Doby George, Wood Gulch and Gravel Creek mineral deposits; future drilling at the Aura Project; the significance of historic exploration activities, results and data; and the ability to expand the existing mineral resources at the Aura Project. Such factors include, among others, risks relating to the ability of exploration activities (including drill results) to accurately predict mineralization; errors in management's geological modelling; management's perceptions of historical trends, current conditions and expected future developments; the ability to realize upon geological modelling; the ability of Western Exploration to complete further exploration activities, including drilling; property and royalty interests in respect of the Aura Project; the ability of the Company to complete and publish a pre-feasibility study on the Aura Project and the timing thereof (if at all); the ability to expand mineral resources beyond current mineral resource estimates; the ability to identify mineral reserves on the Aura Project (if at all); the ability of the Company to obtain required approvals; the results of exploration activities; risks relating to mining activities; the global economic climate; metal prices; dilution; environmental risks; and community and non-governmental actions. Although the forward-looking information contained in this news release is based upon what management believes, or believed at the time, to be reasonable assumptions, Western Exploration cannot assure shareholders and prospective purchasers of securities of the Company that actual results will be consistent with such forward-looking information, as there may be other factors that cause results not to be as anticipated, estimated or intended, and neither Western Exploration nor any other person assumes responsibility for the accuracy and completeness of any such forward-looking information. Western Exploration does not undertake, and assumes no obligation, to update or revise any such forward-looking statements or forward-looking information contained herein to reflect new events or circumstances, except as may be required by law.
For additional information with respect to these and other factors and assumptions underlying the forward-looking statements and forward-looking information made in this news release concerning Western Exploration, please refer to the public disclosure record of Western Exploration, including the management information circular dated November 12, 2021 and the Company's most recent annual and interim financial statements and related management's discussion and analysis, which are available on SEDAR+ (www.sedarplus.ca) under Western Exploration's issuer profile. The forward-looking statements set forth herein concerning Western Exploration reflect management's expectations as at the date of this news release and are subject to change after such date. Western Exploration disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, other than as required by law.
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 news release. No stock exchange, securities commission or other regulatory authority has approved or disapproved the information contained herein.
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