AbraSilver Reports Positive Metallurgical Test Results for JAC Zone With Up To 93% Silver Recoveries & 91% Gold Recoveries
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www.abrasilver.com
AbraSilver Reports Positive Metallurgical Test Results for JAC Zone With Up To 93%
Silver Recoveries & 91% Gold Recoveries
Toronto – June 01, 2023: AbraSilver Resource Corp. (TSX.V: ABRA; OTCQX: ABBRF)
(“AbraSilver” or the “Company”) is pleased to report positive preliminary metallurgical test results
for the new JAC zone at its wholly-owned Diablillos property in Salta Province, Argentina (“Diablillos”
or the “Project”). The program was completed by independent metallurgical consultants, SGS Canada
Inc., at their testing facilities in Lakefield, Ontario.
Key Highlights Include:
Overall recoveries at the JAC and Fantasma deposits range between 86% - 93% for silver
and 82% - 91% for gold.
A substantial percentage of the silver at JAC can be recovered by gravity separation which
increases overall recoveries.
Current testwork confirms that the same process flowsheet can be used to process
mineralization from the Oculto, JAC and Fantasma deposits.
Milling tests have shown that 150 microns is the targeted grind size for the leaching of the
mineralized material at a retention time of 36 hours.
Overall silver and gold recoveries could likely be increased further by grinding finer and with
higher cyanide concentrations. Further metallurgical testwork and trade-off studies are now
underway.
John Miniotis, President and CEO, commented, “We are extremely pleased that the metallurgical
testwork results at JAC demonstrate excellent recovery rates for both silver and gold. These results
show that mineralization at JAC responds very well to conventional processing and recovery
technologies, providing highly positive implications for the future development potential of the project.
The results will be incorporated into our Mineral Resource estimate and Pre-Feasibility Study which
remain on track to be delivered later this year.”
Favorable Recovery Rates vs. Prior Testwork
At the JAC and Fantasma deposits the silver minerals (chlorargyrite and iodargyrite) are easier to
release by grinding, and are more sensitive to cyanide leaching as they occur in argillic alteration,
whereas at Oculto they are mostly held more complexly in vuggy silica host rock.
Table 1 - Summary of Metallurgical Testwork Results for JAC and Fantasma Deposits
Target
Silver
Recoveries
Silver
Head Grades
Gold
Recoveries Gold
Head Grades
% g/t % g/t
JAC &
FANTASMA 86 - 93 142 - 172 82 - 91 0.11 - 0.17
Testwork on JAC and Fantasma samples showed that gravity separation before cyanide leaching
recovers approximately 9% of the silver and 17% of the gold which, when combined with the
subsequent cyanide leaching recoveries, results in total overall recoveries of between 86% and 93%
for silver and between 82% and 91% for gold.
Table 2 below shows gravity plus cyanide leach recoveries at the JAC and Fantasma deposits
compared with the Oculto deposit recoveries announced in the PEA announced in January 2022.
Table 2 – Latest Metallurgical Testwork Results vs. Jan. 2022 PEA Study
Recoveries JAC & Fantasma (May 2023) Oculto PEA Study (Jan.2022)1
Gold 82%-91% 86.0%
Silver 86%-93% 73.5%
Comments Gravity + Cyanidation Cyanidation Only
1Recovery rates for Oculto PEA reflect the life of mine average as per the report published on Jan. 13, 2022 titled “NI 43-101 Preliminary
Economic Assessment Technical Report – Diablillos Project”
A median of 89.5% recoveries for silver and 86.5% for gold at JAC and Fantasma compare favourably
against the 73.5% silver recoveries and 86.0% gold recoveries used for the Preliminary Economic
Assessment (“PEA”) at Oculto. The median silver recovery of 89.5% relative to 73.5% for Oculto is
particularly relevant because the mineralization at the JAC and Fantasma deposits is predominantly
silver.
Figure 1 – Median Recoveries at the JAC & Fantasma Deposits Compared with the Oculto Deposit
JAC drill core samples for metallurgical testing were selected to be volumetrically representative of
the mineralised system, being from the various zones of mineralisation along strike and at depth,
including high, medium and lower grades. Care was taken not to mix alteration zones so that geo-
metallurgical domains can be determined.
Additional metallurgical testing is being conducted on samples from different geo-metallurgical
domains at Oculto in an effort to boost overall recoveries, especially from areas with high silver
grades.
Metallurgical Test Program Overview
This campaign was the first metallurgical testwork program conducted on the new JAC zone,
discovered in August 2022, and on the already known Fantasma deposit. Work completed involved
comminution, gravity, leaching and thickening testwork of fourteen variability composites with twelve
from the JAC zone and two from the Fantasma zone. The results will be incorporated in the upcoming
Mineral Resource estimate (“MRE”) update and Pre-Feasibility Study (“PFS”) for the overall Diablillos
project.
The results confirm that the Diablillos project will have a conventional silver/gold processing plant
flowsheet incorporating crushing, grinding, gravity concentration and intense cyanidation circuit,
cyanide leaching with oxygen addition, counter current decantation (“CCD”) washing thickeners and
Merrill-Crowe precious metal recovery from solution followed by on-site smelting to doré bars.
A summary of the processing flow sheet for the Diablillos project is shown below.
Figure 2 – Simplified Process Flowsheet for the Diablillos Project
Bulk mineralogical investigation determined that quartz, alunite, and iron-oxides were the
major mineral components of the samples, and it is demonstrated that most of the silver will
respond well to direct cyanidation. The JAC composite was used for most of the testing
program, with average head grades of 0.11 g/t gold and 148 g/t silver.
Response to standard gravity separation tests for the recovery of free silver and gold resulted
in average recoveries of 9% and 17%, respectively. As a result, the overall gravity plus
cyanidation recoveries achieved were 86% to 93% for silver and 82% to 91% for gold.
The following optimum whole ore cyanidation conditions were established for the JAC
composite and applied to the variability samples:
• Grind size P80 of 150 μm,
• 45% pulp density (w/w),
• pH of 10.5-11.0 (maintained with lime),
• 4 hours of pre-aeration with air sparging,
• air-sparging during leaching,
• Sodium cyanide (NaCN) concentration of 1.5 g/l maintained for the first 12 hours of leaching
and then allowed to naturally decay for the remaining leach time.
The testwork showed that silver and gold recoveries could likely be further increased by
grinding finer (P80 of 70 μm versus 150 μm) and by increasing cyanide consumption from 1.5
g/l to 2.5 g/l. Further metallurgical testwork and trade-off studies will be conducted to confirm
the optimum process route.
Environmental assessment of the leach tailings samples showed the potential for acid
generation in some samples. On-site humid cell testwork is planned and mitigating measures
will be designed as part of the tailings management strategy.
Settling/thickening and rheology tests were performed on the JAC composite cyanide leach
and cyanide destruction residue, showing a fast-settling rate in response to tested flocculants.
Counter Current Decantation (CCD) modelling was performed as well, resulting in a 4 stages
CCD circuit producing a final wash efficiency of 99.8%
Future Work Programs
Cyanide leach tests will continue on the samples from Oculto, JAC and Fantasma to optimize
recovery and leach time. Drivers to improve recoveries will include stronger cyanide solutions,
grind size of the ore, and leaching residence times.
As gravity separation was successful in concentrating gold and silver at the JAC deposit, it is
proposed that additional testing of gravity separation in advance of cyanidation be carried out
on mineralisation types at Oculto, where there are both gold and silver dominant geo-
metallurgical zones.
At the Diablillos site, humid cell test work is ongoing to evaluate acid rock drainage generation
from the cyanidation tailings under site conditions to support potential mitigating measures in
the tailings management strategy.
Heap leaching test work will be conducted to investigate the possibility of recovering lower
grade material.
About Diablillos
The 80 km2 Diablillos property is located in the Argentine Puna region - the southern extension of the
Altiplano of southern Peru, Bolivia, and northern Chile - and was acquired from SSR Mining Inc. by
the Company in 2016. There are several known mineral zones on the Diablillos property, with the
Oculto zone being the most advanced with over 120,000 metres drilled to date. Oculto is a high-
sulphidation epithermal silver-gold deposit derived from remnant hot springs activity following
Tertiarty-age local magmatic and volcanic activity. Comparatively nearby examples of high
sulphidation epithermal deposits include: Yanacocha (Peru); El Indio (Chile); Lagunas Nortes/Alto
Chicama (Peru) Veladero (Argentina); and Filo del Sol (Argentina).
The most recent Mineral Resource estimate for the Oculto Deposit is shown in Table 3:
Table 3 - Oculto Mineral Resource Estimate – As of October 31, 2022
Category Tonnage
(000 t)
Ag
(g/t)
Au
(g/t)
Contained Ag
(000 oz Ag)
Contained Au
(000 oz Au)
Measured 19,336 98 0.88 60,634 544
Indicated 31,978 47 0.73 48,737 752
Measured &
Indicated 51,314 66 0.79 109,370 1,297
Inferred 2,216 30 0.51 2,114 37
Notes: Effective October 31, 2022. Mineral Resources are not Mineral Reserves and have not demonstrated economic
viability. The Mineral Resource estimate is N.I. 43-101 compliant and was prepared by Luis Rodrigo Peralta, B.Sc., FAusIMM
CP(Geo), Independent Consultant. The mineralization estimated in the Mineral Resource is sub-horizontal with sub-vertical
feeders and a reasonable prospect for eventual economic extraction by open pit methods. For additional information please
see Technical Report on the Diablillos Project, Salta Province, Argentina, dated November 28, 2022, completed by Mining
Plus, and available on www.SEDAR.com.
QA/QC and Core Sampling Protocols
AbraSilver applies industry standard exploration methodologies and techniques, and all drill core
samples are collected under the supervision of the Company’s geologists in accordance with industry
practices. Drill core is transported from the drill platform to the logging facility where drill data is
compared and verified with the core in the trays. Thereafter, it is logged, photographed, and split by
diamond saw prior to being sampled. Samples are then bagged, and quality control materials are
inserted at regular intervals; these include blanks and certified reference materials as well as duplicate
core samples which are collected in order to measure sample representivity. Groups of samples are
then placed in large bags which are sealed with numbered tags in order to maintain a chain-of-custody
during the transport of the samples from the project site to the laboratory.
All samples are received by the SGS offices in Salta who then dispatch the samples to the SGS
preparation facility in San Juan. From there, the prepared samples are sent to the SGS laboratory in
Lima, Peru where they are analyzed. All samples are analyzed using a multi-element technique
consisting of a four-acid digestion followed by ICP/AES detection, and gold is analyzed by 30g Fire
Assay with an AAS finish. Silver results greater than 100g/t are reanalyzed using four acid digestion
with an ore grade AAS finish. Analytical results are statistically processed for final acceptance.
Qualified Persons
David O’Connor P.Geo., Chief Geologist for AbraSilver, is the Qualified Person as defined by National
Instrument 43-101 Standards of Disclosure for Mineral Projects, and he has reviewed and approved
the scientific and technical information in this news release.
About AbraSilver
AbraSilver is an advanced-stage exploration company focused on rapidly advancing its 100%-owned Diablillos
silver-gold project in the mining-friendly Salta province of Argentina. The current Measured and Indicated
Mineral Resource estimate for Diablillos consists of 51.3 Mt grading 66g/t Ag and 0.79g/t Au, containing
approximately 109Moz silver and 1.3Moz gold, with significant further upside potential based on recent
exploration drilling. The Company is led by an experienced management team and has long-term supportive
shareholders including Mr. Eric Sprott. In addition, AbraSilver owns a portfolio of earlier-stage copper-gold
projects including the La Coipita copper-gold project in the San Juan province of Argentina. AbraSilver is listed
on the TSX-V under the symbol “ABRA” and in the U.S. under the symbol “ABBRF”.
For further information please visit the AbraSilver Resource website at www.abrasilver.com, our LinkedIn page
at AbraSilver Resource Corp., and follow us on Twitter at www.twitter.com/abrasilver
Alternatively please contact:
John Miniotis, President and CEO
Tel: +1 416-306-8334
Cautionary Statements
This news release includes certain "forward-looking statements" under applicable Canadian securities
legislation. Forward-looking statements are necessarily based upon a number of estimates and assumptions
that, while considered reasonable, are subject to known and unknown risks, uncertainties, and other factors
which may cause the actual results and future events to differ materially from those expressed or implied by
such forward-looking statements. All statements that address future plans, activities, events or developments
that the Company believes, expects or anticipates will or may occur are forward-looking information. There can
be no assurance that such statements will prove to be accurate, as actual results and future events could differ
materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on
forward-looking statements. When considering this forward-looking information, readers should keep in mind
the risk factors and other cautionary statements in the Company’s disclosure documents filed with the applicable
Canadian securities regulatory authorities on SEDAR at www.sedar.com. The risk factors and other factors
noted in the disclosure documents could cause actual events or results to differ materially from those described
in any forward-looking information. The Company disclaims any intention or obligation to update or revise any
forward-looking statements, whether as a result of new information, future events or otherwise, except 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