Outcrop Silver Achieves Outstanding Lock Cycle Flotation Recoveries: 97% Gold, 93% Silver
Outcrop Silver Achieves Outstanding Lock
Cycle Flotation Recoveries: 97% Gold, 93%
Silver
VANCOUVER, BC
,
Aug. 23, 2023
/CNW/ -
Outcrop Silver & Gold Corporation
(TSXV: OCG)
(OTCQX: OCGSF) (DE: MRG1)
("Outcrop Silver")
is pleased to report outstanding metallurgical
follow-up results from the high-grade Santa Ana silver project. This phase of metallurgical testing
was completed to characterize the produced tailings and their environmental impact, simulate real-
life processing along a locked cycle, and characterize the final products. The metallurgical test work
confirms for the Santa Ana project a premier level recovery based solely on flotation, high quality
and clean precious metal concentrate and a flotation-only non acid-generating tailing.
Highlights
The locked cycle flotation tests confirmed an outstanding gold recovery of 97 % and a
silver recovery of 93 %.
The resulting gold and silver flotation concentrate yielded 9,488 grams per tonne of
silver and 128 grams per tonne of gold.
Lower deleterious elements levels for favourable commercial sale terms.
Both ABA and NAG tests indicate no potential for acid drainage generation from flotation
tailings from Santa Ana.
"The results from our more rigorous locked cycle tests, which simulate a more realistic operating
environment, have confirmed an outstanding gold recovery of 97% and a silver recovery of 93%,"
commented
Guillermo Hernandez
, Vice President Exploration. "These results, combined with positive
findings on acid generation and the very low content of deleterious elements, are pivotal from both a
technical and environmental standpoint. These insights are crucial as we continue to refine our
understanding and derisking of Santa Ana, one of the premier grade silver deposits in the world."
"The latest metallurgical results signify a promising future for the Santa Ana project. Achieving such
high recoveries through flotation alone, combined with the production of a marketable clean high-
grade concentrate, underscores the project's immense potential," commented
Ian Harris
, Chief
Executive Officer. "Furthermore, the environmentally conscious test work indicates clean tailings,
which aligns perfectly with our commitment to responsible mining. This is not just good news—it's a
testament to the project's viability and our dedication to advancing it in the most sustainable and
efficient manner."
Metallurgical Test Work
Outcrop Silver prepared four core sample composites using coarse laboratory rejects (see news
release dated
February 23, 2022
). Two samples for each vein as follow: samples POR-01 and
POR-02 for the La Porfia vein and samples PAR-01 and PAR-02 for Paraiso vein. Each composite
weighted approximately 50 kilograms, and the samples represented two metallurgical domains: high-
grade and low-grade. The high-grade composites represent the average grade in the ore-shoot,
while the low-grade represents Outcrop Silver's "significant result" threshold. SGS Metallurgical
Services Chile has conducted all preparation and testing to date.
The latest metallurgical work consists of kinetic flotation locked circuit tests on the PAR-2 sample
from the Megapozo shoot of the Paraiso vein (see news release dated
November 03, 2022
) and
Acid-Drainege Generation potential assessment. Table 1 shows the metallurgical balance, final
recovery of 97.14% for gold and 92.85% for silver, producing a concentrate grading of 128.74
grams per tonne of gold and 9,488 grams per tonne of silver.
Grades
Recoveries %
Product
Mass %
Ag g/t
Au g/t
Fe %
S %
Ag
Au
Fe
S
Final Concentrate
5.17
9,488
128.74
35.36
46.75
92.85
97.14
31.89
74.83
Tails
94.83
40
0.21
4.12
0.86
7.15
2.86
68.11
25.17
Calculated Head
100.00
512
6.30
6.02
3.54
100.00
100.00
100.00
100.00
Assayed Head
539
6.14
7.27
3.81
Table 1. Summary Metallurgical Balance
Mineral Concentrate Characterization
The resulting concentrate was also chemically characterized with ICP at SGS Chile under the
analytical method ICP040B for a complete 43-element screening to determine concentrations of
potential deleterious elements. The arsenic content is 0.43%, and the antimony is 0.09% showing
acceptable levels for commercial terms of sale. Such characterizations are vital, offering insights into
the concentrate's quality and ensuring it aligns with industry standards for marketability.
As %
Co ppm
Cu %
Fe %
Mn ppm
Pb %
Sb %
Zn %
0.43
118
0.35
36.96
49
5.93
0.09
6.02
Table 2. Summary of potential deleterious elements
Particle Mineral Analysis (PMA) and Trace Mineral Search (TMS) for mineralogical characterization
of the gold and silver concentrate through QEMSCAM performed at SGS Chile allowed to determine
the majority of gold is present as electrum with the silver proportion ranging from 57 to 86%. The
electrum is closely related to silver sulfides, pyrite, sphalerite, and galena. TMS also determined the
lack of free gold grains in the concentrate. On the other hand, forty percent of silver minerals are
free and as sulfides, like Argentite, and are associated with pyrite, galena, sphalerite, and electrum.
Net Acid Generation (NAG) and Acid-Base Accounting (ABA) Test
The NAG test is a static test used to predict the generation of acid rock drainage during and after a
mining operation. It is considered a stand-alone prediction tool, and it is based on the chemical
reaction to accelerate the oxidation of sulfide minerals in a sample.
The ABA test is the most commonly used static method for characterizing mining waste. It is a
screening method for determining the mine waste's acid generation and neutralization potential. The
ABA test includes determining the waste's sulfur/sulfide content.
The tails from the locked cycle flotation tests were analyzed with NAG and ABA tests. The NAG and
ABA static tests highly indicate the ability to produce non-acid generating tails, offering significant
environmental benefits. Such outcomes align with Outcrop Silver's dedication to minimizing
environmental impact. As the project progresses, future testing will include dynamic test work to
further confirm these positive results.
Next Steps
Outcrop Silver plans to conduct additional metallurgical studies on different vein composites and an
overall representative composite of the Santa Ana project, following the recommendations from the
recent test work report. Furthermore, we will explore additional recovery methods and refine the
flow sheet to further optimize the project, ensuring the best balance between efficiency and
sustainability.
About Santa Ana
The 100% owned Santa Ana project comprises 27,000 hectares, 190 kilometres from
Bogota,
Colombia
. Santa Ana consists of regional-scale parallel vein systems covering a majority of the
Mariquita District. The Mariquita District is
Colombia's
highest-grade primary silver district, where
mining records date to at least 1585, with historic silver grades reported being among the highest in
Latin America
from dozens of mines.
Santa Ana maiden resource estimate contains an estimated indicated resource of 24.2 million
ounces silver equivalent at a grade of 614 grams per tonne silver equivalent and an inferred mineral
resource of 13.5 million ounces silver equivalent at a grade of 435 grams per tonne silver equivalent,
based on the NI 43-101 Technical Report titled "Santa Ana Property Mineral Resource Estimate,"
dated
June 8, 2023
, and prepared by AMC Mining Consultants. The resource is comprised of the
seven vein systems (commonly containing multiple parallel veins and multiple ore shoots) discovered
to date – Santa Ana (
San Antonio
,
Roberto Tovar
,
San Juan
shoots); La Porfia (La Ivana); El
Dorado (El Dorado, La Abeja shoots); Paraiso (Megapozo); Las Maras; Los Naranjos and La
Isabela.
Veins with similar high grade and thickness exist along strike toward the south, forming a high-grade
silver enriched trend that extends for 30 kilometres. Outcrop Silver's exploration team has identified
numerous additional veins based on high-grade samples from outcrop and historical workings that
have yet to be drill tested. Outcrop Silver remains focused on identifying new vein targets with high-
grade potential, and adding substantially derisked mineralized silver-bearing veins that will increase
the published maiden resource.
About Outcrop Silver
Outcrop Silver is advancing the Santa Ana high-grade silver deposit with exploration activities aiming
to expand the current mineral resource. Santa Ana is being advanced by a highly disciplined and
seasoned professional team with decades of experience in
Colombia
.
Qualified Person
Edwin Naranjo Sierra
is the designated Qualified Person for this news release within the meaning of
the National Instrument 43-101 (NI 43-101) and has reviewed and verified the technical information in
this news release. Mr. Naranjo has an MSc degree in Earth Science and is a Fellow of the
Australasian Institute of Mining and Metallurgy (FAusIMM) and of the Society of Econimic Geology.
ON BEHALF OF THE BOARD OF DIRECTORS
Ian Harris
Chief Executive Officer
+1 604 294 9039
www.outcropsilverandgold.com
Kathy Li
Vice President Investor Relations
+1 778 783 2818
Neither the TSX Venture Exchange nor its Regulation Services Provider (as such term is defined in
the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of
this release. Certain information contained herein constitutes "forward-looking information" under
Canadian securities legislation. Generally, forward-looking information can be identified by the use
of forward-looking terminology such as "potential", "we believe", or variations of such words and
phrases or statements that certain actions, events or results "will" occur. Forward-looking
statements are based on the opinions and estimates of management as of the date such
statements are made and they are subject to known and unknown risks, uncertainties and other
factors that may cause the actual results, level of activity, performance or achievements of Outcrop
to be materially different from those expressed or implied by such forward-looking statements or
forward-looking information, including: the receipt of all necessary regulatory approvals, capital
expenditures and other costs, financing and additional capital requirements, completion of due
diligence, general economic, market and business conditions, new legislation, uncertainties
resulting from potential delays or changes in plans, political uncertainties, and the state of the
securities markets generally. Although management of Outcrop have attempted to identify
important factors that could cause actual results to differ materially from those contained in
forward-looking statements or forward-looking information, there may be other factors that cause
results not to be as anticipated, estimated or intended. 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 and forward-looking information. Outcrop will not update any
forward-looking statements or forward-looking information that are incorporated by reference
herein, except as required by applicable securities laws.
SOURCE
Outcrop Silver & Gold Corporation
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For further information:
Ian Harris, Chief Executive Officer, +1 604 294 9039,
[email protected], www.outcropsilverandgold.com; Kathy Li, Vice President Investor
Relations, +1 778 783 2818, [email protected]
CO: Outcrop Silver & Gold Corporation
CNW 07:00e 23-AUG-23