Outcrop Silver Reports Exceptional Metallurgical Results - Confirming Recoveries of 93.4% Silver and 96.7% Gold
Outcrop Silver Reports Exceptional
Metallurgical Results - Confirming Recoveries
of 93.4% Silver and 96.7% Gold
VANCOUVER, BC
,
April 5, 2023
/CNW/ -
Outcrop Silver & Gold Corporation
(TSXV: OCG)
(OTCQX: OCGSF) (DE: MRG1)
("Outcrop Silver")
is pleased to report excellent updated
metallurgical results from the 100% owned high grade Santa Ana silver project in
Colombia
. The
second phase of metallurgical testing was completed to confirm high recoverability using flotation
and is a critical de-risking milestone for Santa Ana. The results will be incorporated in Santa Ana's
upcoming maiden resource report.
Highlights
Testwork confirms flotation is an attractive recovery option for Santa Ana with excellent
recoveries and concentrate grades
Highly commerciable flotation concentrate grades of 12,133 grams per tonne silver and
172 grams per tonne gold
Excellent global recoveries for silver and gold confirmed at 93.4% and 96.7%,
respectively, consistent with previous metallurgical testing
Flotation circuit times range between 2.5 and 10 minutes for cleaning stages with an
efficiency of 97.6%, representing a standard residence time for a potential future
operation
Milling tests have shown that 105 microns is the optimum grain size for the flotation of
the mineralized material
"We are delighted our metallurgical testing results confirm flotation as a viable option for the Santa
Ana project with recoveries greater than 93%, and marketable concentrates of 12,133 grams per
tonne silver and 172 grams per tonne gold with testwork performed with standard residence times
and coarse grind," commented
Guillermo Hernandez
, Vice President of Exploration. "Confirming
flotation as a silver and gold recovery option with potentially high payables greatly reduces the
potential environmental footprint, operating costs and permitting risk of the project."
Outcrop Silver prepared four sample composites, two per mineralized shoot, from Ivana (POR-1 and
POR-2) and Megapozo (PAR-1 and PAR-2) from coarse laboratory rejects. Each composite
weighed approximately 50 kilograms, and the samples represent two metallurgical domains: high-
grade and low-grade. The high-grade composites represent the average grade in the shoot,
whereas the low-grade is estimated at 200 g AgEq/t, the threshold used to define significant silver
equivalent grades. SGS Metallurgical Services Chile has conducted all preparation and testing.
The phase two metallurgical work consists of kinetic flotation circuit tests on the PAR-2 sample from
the Megapozo target of the Paraiso vein. Table 1 shows the metallurgical balance per cleaner stage
with a global recovery of 93.4% for silver and 96.9% for gold. The third cleaner stage produced a
concentrate grading 12,133 grams per tonne of silver and 172 grams per tonne of gold.
Flotation times in the cleaner stages were 10, 6 and 2.5 minutes for the first, second and third
stages, respectively. Additionally, the total time for the scavenger stage was 15 minutes aiming to
maximize gold and silver recovery.
Product
Mass
Assays
Distribution %
g
%
Zn
Pb
Ag
Au
Zn
Pb
Ag
Au
%
%
g/t
g/t
%
%
%
%
3rd Cleaner Concentrate
46.3
2.3
7.37
8.16
12,133
172
35.4
56.0
55.2
62.9
2nd Cleaner Concentrate
76.3
3.8
6.19
6.97
10,601
146
49.0
78.7
79.3
87.9
1st Cleaner Concentrate
90.4
4.5
5.50
6.10
9,296
126
51.7
81.7
82.5
89.9
Tails
1,854
6.9
0.16
0.03
37
0.2
31.1
8.3
6.6
3.1
Table 1. Summary results with metallurgical balance per stage
.
Global Recovery
Zn %
Pb %
Ag %
Au %
68.9
91.7
93.4
96.9
Table 2. Global recoveries from open circuit kinetic test.
Figure 1-1. Recoveries and concentrate quality per cleaner stage. (CNW Group/Outcrop Silver &
Gold Corporation)
Figure 1-2. Recoveries and concentrate quality per cleaner stage. (CNW Group/Outcrop Silver &
Gold Corporation)
The particle size mass distribution shows more than 80% of sulphides are liberated from milling
down to 100 microns. The currently selected grain size for the flotation tests is 105 microns for initial
milling (Figure 2).
Figure 2. Particle size distribution in sulphide phases. (CNW Group/Outcrop Silver & Gold
Corporation)
SGS Metallurgical Services Chile is currently performing locked-circuit flotation tests following the
same reagent and residence times as used in the open circuit testing (Figure 3).
Figure 3. Locked-circuit flotation flow chart. (CNW Group/Outcrop Silver & Gold Corporation)
QA/QC
Core and rock samples are sent to either Actlabs or SGS in
Medellin, Colombia
, for preparation and
AA assaying on Au and Ag; Pb and Zn for Actlabs as well and then sent to SGS
Lima, Peru
, for
multi-element analysis. Samples sent to Actlabs are then shipped to Actlabs Mexico for multi-
element analysis. In line with QA/QC best practice, approximately three control samples are inserted
per twenty samples (one blank, one standard and one field duplicate). The samples are analyzed for
gold using a standard fire assay on a 30-gram sample with a gravimetric finish when surpassing over
limits. Multi-element geochemistry is determined by ICP-MS using aqua regia digestion. Comparison
to control samples and their standard deviations indicate acceptable accuracy of the assays and no
detectible contamination.
About Santa Ana
The 100% owned Santa Ana project comprises 27,000 hectares located in the northern Tolima
Department,
Colombia
, 190 kilometres from
Bogota
. The project consists of five or more regional
scale parallel vein systems across a trend 12 kilometres wide and 30 kilometres long. The Santa
Ana project covers a majority of the Mariquita District, where mining records date to at least 1585.
The Mariquita District is the highest-grade primary silver district in
Colombia
, with historic silver
grades reported to be among the highest in
Latin America
from dozens of mines. Historic mining
depths support a geologic and exploration model for composite mesothermal and epithermal vein
systems having mineralization that likely extends to great depth. At Santa Ana, it is unlikely that there
is sharp elevation restriction common to high-grade zones in many epithermal systems with no
mesozonal component. The extremely high silver and gold values on Santa Ana reflect at least three
recognized overprinting mineralization events.
At the core Royal Santa Ana project, located at the northern extent of just one of the regional vein
systems controlled by Outcrop Silver, eight vein systems (commonly containing multiple parallel veins
and multiple ore shoots) have been discovered to date – Santa Ana (
San Antonio
,
Roberto Tovar
,
San Juan
shoots); La Porfia (La Ivana hanging-wall and footwall); El Dorado (El Dorado, La Abeja
shoots); Paraiso (Megapozo); Las Maras; Los Naranjos; Espiritu Santo and La Isabela. The Espiritu
Santo and La Isabela veins are not included in the upcoming resource as they are still being defined.
The veins can show both high-grade silver and high-grade gold mineralization, and low-angle veins
appear to connect to more common high-angle veins.
Outcrop Silver drilling indicates that mineralization extends from surface or near surface to depths of
at least 370 metres. Cumulatively, over 60 kilometres of mapped and inferred vein zones occur on
the Santa Ana project. The Frias Mine on the south-central part of the project, 16 kilometres south
of the Royal Santa Ana Mines, produced 7.8 million ounces of silver post-production in the Spanish
colonial era at a recovered grade of 1.3 kg Ag/t. The Frias Mine is considered an analogue to each
of the thirteen shoots discovered to date by Outcrop Silver. Numerous priority drill targets have been
discovered along this 16 kilometres trend with outcropping veins up to 4.7 metres wide and surface
values up to 9,740 grams silver per tonne.
About Outcrop Silver
Outcrop Silver is rapidly advancing the Santa Ana high-grade silver discovery with ongoing expansion
drilling and an initial resource to be released in the coming months. Outcrop Silver is also
progressing exploration on four gold projects with world-class discovery potential in
Colombia
. These
assets are being advanced by a highly disciplined and seasoned professional team with decades of
experience in Colombia.
Qualified Person
The technical information in this news release has been approved by Joseph P Hebert, a qualified
person as defined in NI43-101 and President and Chief Executive Officer of Outcrop Silver.
ON BEHALF OF THE BOARD OF DIRECTORS
Joseph P Hebert
Chief Executive Officer
+1 775 340 0450
www.outcropsilverandgold.com
Kathy Li
Director of 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
Silver 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 Silver 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 Silver 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:
Joseph P Hebert, Chief Executive Officer, +1 775 340 0450,
[email protected], www.outcropsilverandgold.com; Kathy Li, Director of
Investor Relations, +1 778 783 2818, [email protected]
CO: Outcrop Silver & Gold Corporation
CNW 07:00e 05-APR-23