TSX Venture Exchange Symbol: NCX
HIGHLIGHTS
- The recently completed metallurgical tests improved the
copper and gold recovery rates at the Red Dog Deposit by an average
of 5% and 65% respectively, compared to the tests forming the bases
for estimates used in the previously published PEA
- Metallurgical tests also demonstrate potential to recover
silver and rhenium metal content, which was previously excluded
from the PEA economics
- The previously published PEA is being updated to include
upside potential related to higher gold and copper recovery rates,
higher metal prices, and the inclusion of silver and rhenium metal
recovery
VANCOUVER, BC, Oct. 2, 2020 /CNW/ - Northisle
Copper and Gold Inc. (TSXV: NCX) ("Northisle" or the "Company")
is pleased to report that preliminary metallurgical test results
demonstrate a significant improvement in recoveries of copper and
gold for the Red Dog Deposit at its 100%-owned North Island Project
located in British Columbia,
Canada.
The test work was designed to investigate alternative flotation
parameters to improve the recovery rates of copper and gold in the
Red Dog Deposit mineralization. The results demonstrate that the
average copper and gold recovery rates improved by 5% and 65%
respectively, compared to tests used for the Preliminary Economic
Assessment ("PEA") published in September
2017.
In addition, the metallurgical test work included assaying and
evaluating the recoveries of rhenium and silver which were not
included in earlier test work and in the PEA economics. Results
demonstrate rhenium recoveries of 69.4% and silver content in the
concentrate of 15.1 g/t.
Following the previously announced successful metallurgical
results obtained for the Hushamu Deposit, Northisle expects to
update the PEA to incorporate upside potential related to the
expected higher gold and copper recovery rates, inclusion of silver
and rhenium metal recovery at Red Dog and Hushamu deposits as well
as the higher metal prices.
John McClintock, President and
CEO stated: "These results are very positive as they are expected
to significantly improve the economics of our North Island Project.
Given this success, we are eager to update our PEA to reflect the
upside potential of higher copper and gold recovery rates,
inclusion of silver and rhenium metal recovery, and higher metal
prices."
TEST PROGRAM DETAILS
The metallurgical test program was completed by SGS Canada Inc.
(SGS) at their laboratory facility in Burnaby, BC. The test work was done on an
approximately 50 kg composite sample of core from drill holes
RD16-01, RD16-02 and RD16-06. The samples comprising the composite
represent a range of high and lower grade mineralization. The
results of the lock cycle test are presented in the table below.
For comparison, the results of the cleaner tests used for the PEA
are presented in Table 2. The composites for the earlier
metallurgical work were prepared from core samples from
H14-05.
Detailed test work included: sample preparation, sample
characterization, batch rougher batch cleaner and lock cycle test
work. Modifications to the original flotation conditions of the
2016 work included, a regrind of the rougher concentrate to 20um,
new reagent scheme and a three stage cleaner circuit.
The results of the metallurgical tests demonstrated that the
copper recoveries improved to 89.8% from 85.7%. Gold recoveries
improved to 53.0% from 33%.
Table 1:
SGS Labs Results Lockcycle Tests
|
Calculated Feed grade
(% or gpt)
|
PG
(um)
|
Concentrate grade
(% or gpt)
|
Recovery
%
|
|
Cu
|
Au
|
Mo
|
Ag
|
Re
|
|
Cu
|
Au
|
Mo
|
Ag
|
Re
|
Cu
|
Au
|
Mo
|
Ag
|
Re
|
|
Red Dog
|
0.33
|
0.51
|
0.005
|
0.47
|
0.32
|
98
|
26.5
|
24.5
|
0.30
|
15.1
|
20.2
|
89.8
|
53.0
|
73.5
|
35.5
|
69.4
|
Table 2:
2016 Base Met
Cleaner Tes
|
Calculated Feed
grade
(% or gpt)
|
PG
(um)
|
Concentrate grade
(% or gpt)
|
Recovery %
|
|
Cu
|
Au
|
Mo
|
Ag
|
Re
|
|
Cu
|
Au
|
Mo
|
Ag
|
Re
|
Cu
|
Au
|
Mo
|
Ag
|
Re
|
|
Red Dog
|
0.34
|
0.53
|
.007
|
na
|
na
|
100
|
24.2
|
14.3
|
na
|
na
|
na
|
85.7
|
32.2
|
na
|
na
|
na
|
ABOUT THE NORTH ISLAND PROJECT
The
100%-owned North Island Project consists of the Hushamu and nearby
Red Dog deposits, with Mineral Resources summarized in the below
table.
Table 3:
North Island Project Resources as
at December 31, 2018
|
|
Tonnes,
'000
|
|
Grade
|
|
Contained Metal
|
|
Cu, %
|
Au, g/t
|
Mo, %
|
Re, ppm
|
Cu Eq, %
|
|
Cu, B lb
|
Au, Moz
|
Mo, M lb
|
Re, Kg x 1000
|
Cu eq, B lb
|
Au eq, Moz
|
|
|
|
|
Red Dog
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Indicated
|
36,568
|
0.27
|
0.38
|
0.005
|
|
0.52
|
|
0.22
|
0.45
|
4.0
|
|
0.42
|
0.99
|
|
Inferred
|
1,774
|
0.20
|
0.30
|
0.003
|
|
0.39
|
|
0.01
|
0.02
|
0.1
|
|
0.02
|
0.04
|
|
Hushamu
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Indicated
|
305,180
|
0.24
|
0.28
|
0.008
|
0.54
|
0.43
|
|
1.62
|
2.75
|
53.8
|
165
|
2.92
|
6.97
|
|
Inferred
|
189,640
|
0.19
|
0.24
|
0.007
|
0.35
|
0.36
|
|
0.79
|
1.46
|
29.3
|
66
|
1.49
|
3.56
|
|
Total
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Indicated
|
341,743
|
0.24
|
0.29
|
0.008
|
0.48
|
0.44
|
|
1.83
|
3.2
|
57.8
|
165
|
3.34
|
7.96
|
|
Inferred
|
190,788
|
0.19
|
0.24
|
0.007
|
0.35
|
0.36
|
|
0.80
|
1.48
|
29.4
|
66
|
1.51
|
3.60
|
|
Mineral Resource
estimates follow the Canadian Institute of Mining, Metallurgy and
Petroleum ("CIM") definitions standards for Mineral Resources and
Reserves and have been completed in accordance with the Standards
of Disclosure for Mineral Projects as defined by National
Instrument 43-101. The NI 43-101 reports co-authored by P Burt PGeo
and B Game PGeo documenting the resource estimate available on the
company's website and filed on SEDAR. Reported tonnage and grade
figures have been rounded from raw estimates to reflect the
relative accuracy of the estimate. Minor variations may occur
during the addition of rounded numbers. Mineral Resources that are
not Mineral Reserves do not have demonstrated economic viability.
Copper and gold equivalent calculated using US$3.10/lb Cu,
US$1300/oz Au and US$9.00/lb Mo and is not adjusted for mining and
metallurgical recoveries as these remain uncertain. The formula
used is as follows: CuEQ = (Cu% x 22.0462 x 3.10) + (Au g/t x
1300.00/ 31.1035) + (Mo% x 22.0462 x 9.00)/22.046x3.1. AuEQ =(Cu% x
22.0462 x 3.10) + (Au g/t x 1300.00/ 31.1035) + (Mo% x
22.0462 x 9.00)/(1300/31.1035). Rhenium values have not been used
in the cut-off grade or Cu or gold Equivalent
calculations.
|
In September 2017, Northisle
published the results of a PEA which demonstrated the potential
technical and economic viability of the project constructed as an
open-pit mine, with a concentrator processing nominally 75,000
tonnes/day (27Mtpa) with the results summarized in the below table.
This PEA is expected to be updated to reflect the results from the
metallurgical tests described in the sections above.
Table 4:
North Island Project PEA Summary
|
LIFE OF MINE PHYSICALS
|
|
|
Mine life, years
|
22 years
|
|
Strip ratio, w:o
|
0.72
|
|
Throughput
|
27.4Mtpa
|
|
Mineralization inventory
|
600Mt
|
|
Copper grade
|
0.18%
|
|
Gold grade
|
0.24g/t
|
|
Molybdenum grade
|
0.01%
|
|
Pyrite grade
|
9%
|
|
LOM production
|
|
|
Copper
|
1.9B lb
|
|
Gold
|
1.8Moz
|
|
Molybdenum
|
55M lb
|
|
Pyrite
|
17B lb
|
|
Copper equivalent, M lb pa
|
3.1B lb
|
|
Gold equivalent, koz
|
7.4Moz
|
|
AVERAGE ANNUAL PRODUCTION
|
|
|
Copper, M lb
|
82M lb
|
|
Gold, koz
|
79koz
|
|
Molybdenum, M lb
|
3M lb
|
|
Pyrite, kt
|
0.64Kt
|
|
Copper equivalent, M lb
|
141M lb
|
|
Gold equivalent, koz
|
335koz
|
|
AVERAGE ANNUAL PRODUCTION COSTS
|
|
|
Copper C1
Cash Costs net of by-products,
US$/lb
|
$0.88/lb
|
|
Copper AISC net of by-products,
US$/lb
|
$1.22/lb
|
|
Copper equivalent AISC, US$/lb Cu eq
|
$2.00/lb
|
|
ld equivalent AISC, US$/oz Au eq
|
$840/oz
|
|
ECONOMICS
|
|
|
After-tax NPV5%, US$m
|
$757m
|
|
After-tax NPV8%, US$m
|
$413m
|
|
After-tax IRR, %
|
14%
|
|
The commodity
prices used are as follows: US$ 3.10/lb Cu, US$ 1,300/oz Au, US$
9.00/lb Mo, US$ 9/t Py with a CAD/USD of 0.75. For more
information, please consult the 2017 PEA available on SEDAR under
the Company's profile or on Northisle's website.
|
For more information on Northisle please visit
the Company's website at www.Northisle.ca.
John McClintock, P. Eng is the
Qualified Person who reviewed and approved the scientific and
technical disclosure in this news release.
On behalf of Northisle Copper and Gold Inc.
John McClintock, P. Eng
President, CEO and Director www.northisle.ca
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.
This news release contains forward-looking statements. These
forward-looking statements are based upon the reasonable beliefs of
Northisle and its management as of the date of this news release;
however, forward-looking statements involve risks and uncertainties
and are based upon factors that may change and assumptions that may
prove, with the passage of time, to be incorrect as a result of
exploration and other risk factors associated with mineral
exploration and development that are beyond the control of
Northisle. Accordingly, undue reliance should not be placed upon
such statements. If factors materially change or assumptions are
materially incorrect, the actual results, performance or
achievements of Northisle may be materially different from any
future results, performances or achievements expressed or implied
by such forward-looking statements. Northisle does not undertake
any obligation to update or revise any forward-looking statements
to reflect new information, future events or otherwise, except as
required by applicable law.
SOURCE NorthIsle Copper and Gold Inc.