TSX-V: GBR
VANCOUVER, BC, Jan. 27, 2021 /CNW/ - Great Bear Resources Ltd.
(the "Company" or "Great Bear") (TSXV: GBR) (OTCQX: GTBAF) today
reported gold recovery test results from its 100% owned flagship
Dixie Project, in the Red Lake
district of Ontario.
Chris Taylor, President and CEO
of Great Bear said, "We are very pleased to report that our first
metallurgical tests from the Dixie Limb zone have recovered
88 – 97.5 % of head grade gold values from conventional cyanidation
bottle roll leach tests. These results confirm gold
mineralization at the Dixie Limb yields similar very high gold
recoveries to those previously reported from the Hinge zone.
Over the coming months we will periodically release gold recovery
results from representative samples originating from all of our
gold zones including the LP Fault."
Metallurgical tests confirm very high gold recoveries with
minimal impact from either accessory sulphides or the argillite
host rocks which are frequently present in the Dixie Limb
zone. Table 1, Table 2, and Figure
1.
High Sulphide Samples
The Dixie Limb zone contains both low and high sulphide content
mineralization types. Dixie Limb zone gold mineralization
with low accessory sulphide content within quartz veins is
mineralogically indistinguishable from the adjacent Hinge zone
mineralization, which previously yielded very high gold recoveries
of 95 – 97% (November 12, 2020).
This material was not re-tested.
Four high accessory sulphide (pyrrhotite and pyrite
dominated) samples were tested for the first time using the same
metallurgical processes as were previously applied at the Hinge
zone. Additionally, lead nitrate, a common additive to gold
recovery circuits at deposits containing significant accessory
pyrrhotite, was added to two of the high sulphide samples.
Gold recoveries were very high for all samples, returning
similar results to Hinge zone low-sulphide samples.
- More finely ground material yielded slightly higher recoveries
(93.1% for more coarsely ground versus 96.1% for more finely ground
material).
- Faster gold dissolution kinetics and slightly higher gold
recoveries were noted for the samples treated with lead nitrate
(96.1% without lead nitrate versus 96.9% and 96.7% with).
Table 1: Gold recoveries from Dixie Limb zone
material with high sulphide accessory mineral content.
Test
ID
|
NaCN
Concentration
(g/L)
|
Lead
Nitrate
(g/t)
|
%
Solids
|
Primary
Grind (p80,
µm)
|
48 hr Au
Recovery
(%)
|
Cyanide
Consumption
(NaCN, g/t)
|
Calculated
Head Grade
(Au, g/t)
|
CN-5
|
1.0
|
0
|
40
|
121
|
93.1
|
1.11
|
8.99
|
CN-6
|
1.0
|
0
|
40
|
74
|
96.1
|
1.91
|
8.92
|
CN-11
|
1.0
|
250
|
40
|
76
|
96.9
|
1.55
|
9.35
|
CN-12
|
1.0
|
250
|
40
|
77
|
96.7
|
1.35
|
8.80
|
Figure 1: Dixie Limb zone gold recovery curves
showing time-weighted recoveries from high sulphide material.
Argillite Samples
Gold mineralized argillite is present at the Dixie Limb zone but
not in the other gold zones at Dixie. Six gold
mineralized argillite samples were tested using the same
metallurgical processes applied to the Hinge zone and the high
sulphide Dixie Limb zone samples, i.e. variations in primary grind
size and addition of lead nitrate. A higher cyanide
concentration was also analyzed for the first time.
All gold recoveries in all conditions were very high, similar
to non-argillite Hinge and Dixie Limb zone samples.
- Finer grind size had no effect on gold recoveries, which were
high for both coarse and fine grinds (samples CN-3 and CN-4; 92.9%
and 88.3% respectively).
- Increased cyanide concentration yielded a slight increase in
gold recovery (sample CN-9; 97.5%).
- In the argillite material, the addition of lead nitrate
increased the rate of gold dissolution, while reducing the overall
consumption of cyanide. Gold recoveries were also modestly
increased by the addition of lead nitrate (samples CN-7, CN-8 and
CN-10; 97.0%, 97.4% and 97.1% respectively).
Table 2: Gold recoveries from Dixie Limb zone
material hosted by argillite.
Test
ID
|
NaCN
Concentration (g/L)
|
Lead
Nitrate (g/t)
|
%
Solids
|
Primary
Grind (p80, µm)
|
48 hr Au
Recovery (%)
|
Cyanide
Consumption
(NaCN, kg/t)
|
Calculated
Head Grade
(Au, g/t)
|
CN-3
|
1.0
|
0
|
40
|
138
|
92.9
|
1.10
|
10.07
|
CN-4
|
1.0
|
0
|
40
|
77
|
88.3
|
4.47
|
10.89
|
CN-7
|
1.0
|
50
|
40
|
78
|
97.0
|
1.66
|
10.37
|
CN-8
|
1.0
|
250
|
40
|
76
|
97.4
|
1.43
|
11.06
|
CN-9
|
2.0
|
0
|
40
|
74
|
97.5
|
3.30
|
11.49
|
CN-10
|
1.0
|
250
|
40
|
79
|
97.1
|
1.56
|
9.35
|
Figure 2: Dixie Limb zone gold recovery curves
showing time-weighted recoveries from Argillite material.
Impact of Metallurgical Studies To Date
Metallurgical results to date suggest similar gold recovery
processes are applicable to both the Dixie Limb and Hinge
zone. Metallurgical testing of samples from the LP Fault zone
is underway, with results expected periodically over the remainder
of 2021.
The Company will also begin gravity circuit gold recovery tests
on samples from all gold zones in 2021.
Details of Dixie Limb Gold Recovery Work
- Ten one kilogram samples were analyzed by Blue Coast Research
Ltd. of Parksville, British
Columbia during these preliminary metallurgical tests.
- These ten samples were taken from two aggregate composites
which had the following representative geological
characteristics:
- A high sulphide composite of 18.96 kilograms representing 20.10
metres of core length, averaging 8.0 g/t gold.
- A sedimentary host (argillite) composite of 18.6 kilograms
representing 11.95 metres of core length, averaging 10.6 g/t
gold.
- Samples were processed through a standard 48 hour bottle roll
procedure at 40% solids, using a 1.0 g/L sodium cyanide solution.
Other conditions, such as grind size and lead nitrate addition,
were varied according to the test objectives.
About the Dixie Project
The Dixie Project is 100% owned, comprised of 9,140 hectares of
contiguous claims that extend over 22 kilometres, and is located
approximately 25 kilometres southeast of the town of Red Lake, Ontario. The project is accessible
year-round via a 15 minute drive on a paved highway which runs the
length of the northern claim boundary and a network of
well-maintained logging roads.
The Dixie Project hosts two principal styles of gold
mineralization:
- High-grade gold in quartz veins and silica-sulphide
replacement zones (Dixie Limb, Hinge and Arrow zones). Hosted
by mafic volcanic rocks and localized near regional-scale D2 fold
axes. These mineralization styles are also typical of the
significant mined deposits of the Red
Lake district.
- High-grade disseminated gold with broad moderate to lower
grade envelopes (LP Fault). The LP Fault is a significant
gold-hosting structure which has been seismically imaged to extend
to 14 kilometres depth (Zeng and Calvert, 2006), and has been interpreted by
Great Bear to have up to 18 kilometres of strike length on the
Dixie property. High-grade gold mineralization is controlled by
structural and geological contacts, and moderate to lower-grade
disseminated gold surrounds and flanks the high-grade intervals.
The dominant gold-hosting stratigraphy consists of felsic sediments
and volcanic units.
About Great Bear
Great Bear Resources Ltd. is a well-financed gold
exploration company managed by a team with a track record of
success in mineral exploration. Great Bear is focused in the
prolific Red Lake gold district in
northwest Ontario, where the
company controls over 300 km2 of highly prospective
tenure across 4 projects: the flagship Dixie Project (100%
owned), the Pakwash Property (earning a 100% interest), the Dedee
Property (earning a 100% interest), the Sobel Property (earning a
100% interest), and the Red Lake North Property (earning a 100%
interest), all of which are accessible year-round through existing
roads.
QA/QC and Core Sampling Protocols
Drill core is logged and sampled in a secure core storage
facility located in Red Lake Ontario. Core samples from the
program are cut in half, using a diamond cutting saw, and are sent
to Activation Laboratories in Ontario, an accredited mineral analysis
laboratory, for analysis. All samples are analysed for gold using
standard Fire Assay-AA techniques. Samples returning over 10.0 g/t
gold are analysed utilizing standard Fire Assay-Gravimetric
methods. Pulps from approximately 5% of the gold mineralized
samples are submitted for check analysis to a second lab.
Selected samples are also chosen for duplicate assay from the
coarse reject of the original sample. Selected samples with
visible gold are also analyzed with a standard 1 kg metallic screen
fire assay. Certified gold reference standards, blanks and
field duplicates are routinely inserted into the sample stream, as
part of Great Bear's quality control/quality assurance program
(QAQC). No QAQC issues were noted with the results reported
herein.
Qualified Person and NI 43-101 Disclosure
Mr. R. Bob Singh, P.Geo, VP
Exploration, and Ms. Andrea Diakow
P.Geo, Exploration Manager for Great Bear are the Qualified
Persons as defined by National Instrument 43-101 responsible for
the accuracy of technical information contained in this news
release.
Results for the metallurgical test program were provided and
approved by Andrew Kelly, P.Eng., of
Blue Coast Research Ltd., a Qualified Person for the purpose of
National Instrument 43-101.
ON BEHALF OF THE BOARD
"Chris
Taylor"
Chris Taylor, President and
CEO
Cautionary note regarding forward-looking
statements
This release contains certain "forward looking statements"
and certain "forward-looking information" as defined under
applicable Canadian and U.S. securities laws, including
forward-looking statements regarding future metallurgical test
work. Forward-looking statements and information can generally be
identified by the use of forward-looking terminology such as "may",
"will", "should", "expect", "intend", "estimate", "anticipate",
"believe", "continue", "plans" or similar terminology. The
forward-looking information contained herein is provided for the
purpose of assisting readers in understanding management's current
expectations and plans relating to the future. Readers are
cautioned that such information may not be appropriate for other
purposes.
Forward-looking information are based on management of the
parties' reasonable assumptions, estimates, expectations, analyses
and opinions, which are based on such management's experience and
perception of trends, current conditions and expected developments,
and other factors that management believes are relevant and
reasonable in the circumstances, but which may prove to be
incorrect.
Forward-looking statements involve various risks and
uncertainties and are based on certain factors and assumptions.
There can be no assurance that such statements will prove to be
accurate, and actual results and future events could differ
materially from those anticipated in such statements. Important
factors that could cause actual results to differ materially from
the Company's expectations, include, but are not limited to,
disruptions relating to the COVID-19 pandemic and uncertainties
relating to the availability and costs of financing, both of which
could result in future metallurgical test work being delayed or
affected.
Great Bear undertakes no obligation to update forward-looking
information except as required by applicable law. Such
forward-looking information represents management's best judgment
based on information currently available. No forward-looking
statement can be guaranteed and actual future results may vary
materially. Accordingly, readers are advised not to place undue
reliance on forward-looking statements or information.
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SOURCE Great Bear Resources Ltd.