TSX: NHK
TORONTO, June 13, 2018 /CNW/ - Nighthawk Gold
Corp. ("Nighthawk" or the "Company") (TSX: NHK) (OTCQX: MIMZF)
is pleased to report an updated Inferred Mineral Resource estimate,
of 50.305 million tonnes with an average grade of 1.62 grams per
tonne gold ("gpt Au") for 2.613 million ounces of gold (see
Table 1) for its 100% owned Colomac Gold Project
("Colomac"), Northwest
Territories, Canada. The resource estimate was prepared by
CSA Global Canada Geosciences Ltd. (CSA Global), Toronto, Ontario, in accordance with National
Instrument 43-101 ("NI 43-101").
The updated resource estimate incorporates a total of 1,088
drill holes totaling 141,013 metres (913 historical drill holes
totaling 85,178 metres, and 175 drill holes totaling 55,835 metres
completed by Nighthawk between 2012 and 2017). Since the 2013
resource estimate, Nighthawk has drilled 145 holes for 44,600
metres which is captured within this latest resource update.
Resource Highlights:
|
|
24.4% increase in
inferred resources
|
Contained gold ounces
increased by 24.4% to 2.613 million ounces with an average grade of
1.62 gpt Au. An updated block cut-off grade of 0.70 gpt Au was used
for the Colomac and Goldcrest deposits and a 0.60 gpt Au cut off
was retained for the Grizzly Bear, 24 and 27 deposits. Overall
tonnage increased by 26.4% to 50.305 million tonnes over
the previous Inferred Mineral Resource estimate of 39.815 million
tonnes with an average grade of 1.64 gpt Au for 2.101 million
ounces gold using a cut-off grade of 0.60 gpt Au (see press release
dated June 17, 2013).
|
Modest average
grade variation within sensitivity analysis
|
Grade sensitivity
table reveals substantial changes in modelled ounces at different
cutoff grades, yet modest average grade variation. Increasing
the cut-off from 0.70 gpt Au to 1.00 gpt Au for the Colomac Main
Sill ("Colomac Main") and Goldcrest Sill
("Goldcrest") deposits alone sees the average grade increase
to 2.08 gpt Au, resulting in a total of 2.085 million modelled
ounces of gold (see Table 2). Alternately, decreasing the cut-off
to 0.50 gpt Au decreases the average grade to 1.35 gpt Au and
results in 2.906 million modelled ounces of
gold1.
|
Zone 1.5 adds
317,000 ounces of gold to the updated resource
estimate
|
The recently
discovered high-grade Zone 1.5 at Colomac adds 317,000 ounces of
gold to the new resource estimate at a grade of 1.85 gpt Au. The
higher-grade core to the zone remains unconstrained, but the
broader enclosing mineralized zone has been drilled an additional
450 metres below the current resource block model where it remains
open and continuously mineralized, demonstrating the exceptional
opportunities that these higher-grade domains represent.
|
Oriented drill
core data improves geological model
|
An updated geological
model incorporates orientated drill core measurements collected
during Nighthawk's 2016 and 2017 drill campaigns and defines the
gold mineralization as relatively flat lying with a broader
distribution than was modelled in the previous resource estimate.
This has effectively limited the delineation of mineralization to a
shorter down dip extent and moderated the localized influence of
higher-grade, previously constrained, mineralization.
|
Colomac Main Sill
accounts for 90.7% of total resources
|
Colomac's five known
gold deposits (Figure 1) outlined in this reporting include the
Colomac Main, Goldcrest, Grizzly Bear, 24 and 27, of which the
Colomac Main accounts for 90.7% of the current resource. All
deposits are open laterally and to depth (Figure 2).
|
Positive
preliminary metallurgy
|
Recent metallurgical
testwork at Colomac confirms favourable recoveries for all process
options, including heap leaching, flotation, and gravity
separation. Gold extraction by flotation ranged from 90.7% - 94.6%.
Cyanidation of ground rock increased gold recoveries significantly
up to 98.0%.
|
|
Note:
|
1.
|
The reader is
cautioned that the figures in this table are not a Mineral Resource
Statement. The figures are only presented to show the sensitivity
of the block model estimates to the selection of cut-off
grade.
|
Dr. Michael Byron, President
& CEO commented, "We are very pleased to see that the
consistent strength and continuity of mineralization hosted by the
Colomac and Goldcrest sills continues to deliver strong resource
growth. It is notable that to date, the deposit has only had
141,013 metres of drilling, yet is tracking to exceed 3 million
ounces with an abundance of real estate not yet explored. The grade
sensitivity table illustrates the deposit's robust nature by
revealing that modest changes in cutoff grades result in
substantial variations in contained ounces but with limited
variations to the average grade. Given that the current resource
contains over 50 million tonnes of mineralized material, a number
that may only account for less than half of its near surface
potential, we believe that assessing a heap leach opportunity for
Colomac is not only warranted, but if proven, could drastically
change the nature of the opportunity.
"Recent advancements in our understanding of the deposit's
controls on mineralization has led to important revisions to the
Colomac geological model. Within the Goldcrest and Colomac sills,
the change to a more broadly distributed mineralization model,
instead of a constrained and steeply dipping one, has resulted in a
more refined and accurate resource estimate, and a substantial
increase in resource tonnes. In addition to the ongoing exploration
at Colomac, we are also drilling several of our regional gold
deposits and showings, building on the gold camp's vastly
underexplored potential beyond Colomac. The first property we
drilled prior to consolidating the camp, the Damoti Lake Gold
Deposit, will be drilled this summer, in preparation for delivering
a maiden resource estimate in early 2019."
Conference Call Details
Management will host a conference call and webcast to discuss
the updated resource estimate on Wednesday
June 13, 2018 at 10:00am ET.
To access the webcast and for further details, please visit the
Company website www.nighthawkgold.com.
NIGHTHAWK GOLD CORP Resource Update
Conference ID#
9279568
Dial-In Numbers:
Toll-free North America: 1-888-231-8191; United Kingdom: 0-800-051-7107
Table 1:
Colomac Gold Project Updated Inferred Mineral
Resource Estimate (Effective at June 13,
2018)
Zone
|
Tonnes
|
Grade
(gpt
Au)
|
Inferred Gold
Ounces
|
Colomac
North
|
11,522,000
|
1.63
|
604,000
|
Colomac
Central
|
18,744,000
|
1.65
|
997,000
|
Colomac
South
|
14,533,000
|
1.65
|
770,000
|
Goldcrest
North
|
1,145,000
|
1.30
|
48,000
|
Goldcrest Main
(formerly Goldcrest South)
|
2,636,000
|
1.60
|
136,000
|
Sub
Total
|
48,580,000
|
1.64
|
2,554,000
|
Grizzly Bear (Not
Updated, No Change)
|
807,000
|
1.04
|
27,000
|
27 (Not Updated, No
Change)
|
528,000
|
1.21
|
20,000
|
24 (Not Updated, No
Change)
|
390,000
|
0.96
|
12,000
|
Sub Total
|
1,725,000
|
1.06
|
59,000
|
Total
|
50,305,000
|
1.62
|
2,613,000
|
|
Notes:
|
1.
|
A block cut-off value
of 0.70 gpt Au was applied to all Colomac and Goldcrest blocks.
Grizzly Bear, 25 and 27 reporting cut off remains at 0.60 gpt
Au.
|
2.
|
Tonnes and ounces
have been rounded to reflect the relative accuracy of the mineral
resource estimate; there-fore numbers may not total
correctly.
|
3.
|
Mineral resources
were calculated with commercial mining software.
|
4.
|
For 2018 updated
Colomac and Goldcrest block models: Drill holes traces showing
lithology and gold grade were reviewed in plan and cross section.
Geological domains were created using LeapfrogTM Implicit
Geological Modelling Software. Assays were composited to regular 1
metre intervals. Colomac assays were capped at 30.00 gpt Au and
Goldcrest assays were capped at 15.00 gpt Au. Block model grade
interpolation was undertaken using Inverse Distance Cubed
(IDW3).
|
5.
|
For 2012 Grizzly
Bear, 24 and 27 block models: Drill holes traces showing lithology
and gold grade were reviewed in plan and cross section to generate
mineralized domains. Assays with each domain were top cut to 31 gpt
Au and then composited to regular 5ft intervals. Block model grade
interpolation was undertaken using Multiple Indicator Kriging
(MIK). Refer to Lee and Trinder (2012).
|
6.
|
The resource estimate
was prepared by Leon McGarry, B.Sc., P.Geo., of CSA
Global.
|
7.
|
Gold price is US$1300
per ounce.
|
8.
|
A default average
specific gravity (SG) value of 2.7 has been used.
|
9.
|
Mineral resource
tonnes quoted are not diluted.
|
10.
|
No measured or
indicated mineral resources or mineral reserves of any category are
identified.
|
11.
|
Mineral resources are
not mineral reserves and by definition do not demonstrate economic
viability. This mineral resource estimate includes inferred mineral
resources that are normally considered too speculative geologically
to have economic considerations applied to them and must not be
converted to a mineral reserve. It is reasonably expected that the
majority of inferred mineral resources could be upgraded to
indicated mineral resources with continued exploration.
|
12.
|
1 troy ounce equals
31.10348 gram
|
Table 2:
Grade Tonnage Sensitivity
Table for the Updated Colomac and Goldcrest Resource Block
Model
Cut Off Grade
(gpt Au)
|
Tonnes
|
Grade
(gpt
Au)
|
Contained
Ounces Au
|
1.0
|
31,172,000
|
2.08
|
2,085,000
|
0.9
|
36,154,000
|
1.93
|
2,237,000
|
0.8
|
41,722,000
|
1.78
|
2,389,000
|
0.7
|
48,580,000
|
1.64
|
2,554,000
|
0.6
|
56,967,000
|
1.50
|
2,729,000
|
0.5
|
67,032,000
|
1.35
|
2,906,000
|
0.4
|
79,800,000
|
1.20
|
3,090,000
|
0.3
|
95,825,000
|
1.06
|
3,270,000
|
0.2
|
115,849,000
|
0.92
|
3,430,000
|
Note: The reader is cautioned that the figures in this
table are not a Mineral Resource Statement. The figures are only
presented to show the sensitivity of the block model estimates to
the selection of cut-off grade.
2018 Mineral Resource Estimate
The mineral resource estimate was prepared by CSA Global,
Toronto, Ontario, in accordance
with NI 43-101 and has been reviewed internally by the Company. The
full technical report will be available on SEDAR within 45 days of
the date of this release. All resources have been assigned to the
inferred category due to the historic nature of a significant
portion of the data and the need for additional verification work.
Mined volumes of the Colomac Main Sill have been deleted from the
current resource model.
Resources were defined using an updated block cut-off grade of
0.70 gpt Au for the Colomac and Goldcrest deposits, and a 0.60 gpt
Au cut off was retained for the Grizzly Bear, 24 and 27 deposits.
The current resource estimate is based on 1,088 drill holes
totaling 141,013 metres (913 historical drill holes totaling 85,178
metres, and 175 drill holes totaling 55,835 metres completed by
Nighthawk between 2012 and 2017, see Table 3).
Table 3:
Nighthawk drilling used in the
Updated Mineral Resource Estimate
Year
|
# of
DDH
|
Metres
Drilled
|
Deposit/Zone
|
2012
|
30
|
11,235
|
Colomac
Zones 2.0 and
3.5
|
2014
|
10
|
3,635
|
Colomac
Zones 1.5, 2.0 and
2.5
|
2014
|
24
|
6,038
|
Goldcrest
Main
|
2015
|
8
|
2,080
|
Colomac
Zone 1.5
|
2016
|
19
|
4,524
|
Colomac
Zones 1.0, 1.5, 2.5,
3.0 and 3.5
|
2016
|
7
|
1,889
|
Goldcrest
Main
|
2016
|
8
|
1,956
|
Goldcrest
North
|
2017
|
56
|
21,167
|
Colomac
Zones 1.0, 1.5,
2.5,
|
2017
|
13
|
3,308
|
Goldcrest
Main
|
Total Drilled by
Nighthawk
|
175
|
55,835
|
Colomac &
Goldcrest
2012 -
2017
|
|
|
|
|
Post 2013
MRE
|
93
|
31,407
|
Total Colomac
2014-2017
|
|
|
|
|
Post 2013
MRE
|
52
|
13,193
|
Total Goldcrest
2014-2017
|
The current study incorporates an updated geological model
refined by orientated core measurements collected by the company
during its 2016 and 2017 drill campaigns. Initial measurements
indicate that mineralized vein sets are generally shallow dipping.
This contrasts with the 2013 resource modelling where steeply
dipping shears and veins were considered the dominant controls to
mineralization and were deemed best represented using a 0.50 gpt Au
grade shell. However, based on the latest drill core orientation
work this is no longer considered valid. Consequently, gold
mineralization is modelled to be more broadly distributed and flat
lying. This change has resulted in the delineation of mineral
resources over a shorter down dip extent resulting in resource
tonnage increases throughout the Colomac deposits. Increased
drilling and the introduction of oriented core measurements has
significantly advanced the understanding of Colomac mineralization,
resulting in a much more refined and robust geological model, which
in turn has generated a more accurate and representative mineral
resource estimate to build upon.
Additions to the Current Resource Estimate Relative to the
2013 Resource Estimate
The high-grade Zone 1.5 at Colomac was discovered by the Company
in 2014, and since then 14,660 metres of drilling has led to the
delineation of 5,347,000 tonnes at an average grade of 1.85 gpt Au
for 317,000 ounces of gold. The new resource modelling method
lacked the necessary information to delineate a constrained domain
to the Zone's central core of higher-grade mineralization.
Instead, the approach treats mineralization as being more broadly
distributed over the width of the mineralized portion of the sill.
Future modelling refinements are expected to allow domaining of the
higher-grade core of this zone with future drilling.
Resource blocks at Zone 1.5 extend 490 metres below
surface. However, two holes drilled by Nighthawk in 2017 to
explore the zone at depth intersected continuous mineralization to
900 metres below surface outside and below the current resource.
Here the zone's pervasive mineralization appears to triple in true
width and remains open (see press releases dated September 18, 2017 and November 28, 2017). New
drilling at Zone 1.5 accounts for the majority of the 118% increase
in gold ounces at Colomac North (Table 1) relative to the 2013
mineral resource estimate and demonstrates the dynamic resource
expansion potential that high-grade zones represent at Colomac.
At Goldcrest Main (formerly referred to as Goldcrest South),
11,246 metres of new drilling extended the maximum depth of the
resource model from 150 metres to 300 metres below surface, where
it remains open. Infill drilling and the availability of new sample
data has allowed the removal of partially assayed historical drill
holes resulting in a higher average modelled thickness. The
increase in the size of the model has added 2.20 million tonnes at
an average grade of 1.50 gpt Au resulting in an additional 106,120
ounces of gold.
Next Steps
A minimum, 25,000 metre drill program was initiated in early
March with three drills to be active on Colomac area resource
expansion targets, as well as on several of the Company's regional
deposits and prospects. At Colomac, exploration for
additional high-grade zones is ongoing, as is drilling to infill
areas in the current resource in preparation for a future resource
update. It is anticipated that the next resource estimate
will include indicated resource numbers for Zone 1.5 and Zone 3.5.
Expanded metallurgical testing is scheduled for 2018 with sampling
of additional zones along the Colomac and Goldcrest sills. This
program will also involve a greater number of tests to continue
evaluating the deposit's heap leach potential.
About the Colomac Gold Project
The Colomac Gold
Project lies within the central portion of Nighthawk's Indin Lake
Gold Property, 220 kilometres northwest of Yellowknife, Northwest Territories. Access is
by winter road from Yellowknife or
year-round by chartered aircraft to a 5,000-foot airstrip at the
former Colomac Mine site. Nighthawk has secured a contiguous land
position fully surrounding the Colomac Gold Project by
consolidating more than 90% of the Indin Lake Greenstone Belt
including the related Indin Lake Gold Camp. The Colomac Gold
Project contains at least five separate gold deposits open in all
dimensions (Colomac Main Sill, Goldcrest Sill, Grizzly Bear, 24 and
27), only one of which, the Colomac Deposit, was historically
mined. Intermittent mining from 1990 to 1997 was limited to three
shallow open pits developed on a steeply dipping differentiated
mafic intrusion (Colomac Main Sill). Historical production is
reported to be 527,908 ounces gold with an average head grade of
1.66 gpt gold. Mining activities impacted only a small portion of
the sill's 7 kilometre mineralized strike length. All mining and
processing equipment and infrastructure have been removed from the
Colomac Property.
Qualified Person
Technical information related to the
mineral resource estimate contained in this news release has been
reviewed and approved by Leon
McGarry, B.Sc., a Senior Resource Geologist with CSA Global,
who is an independent Qualified Person as defined by NI 43-101,
with the ability and authority to verify the authenticity and
validity of this data. The technical report supporting the mineral
resource estimate will be filed on SEDAR within 45 days.
Dr. Michael J. Byron, Ph.D., P.Geo., President & Chief
Executive Officer of Nighthawk, who is the "Qualified Person" as
defined by NI 43-101 for this project, has reviewed and approved of
the technical disclosure contained in this news release.
Technical Information
Nighthawk has implemented a
quality-control program to comply with best practices in the
sampling and analysis of drill core. Drill core samples were
transported in security-sealed bags for analyses at ALS Chemex
Assay Laboratory in Vancouver, BC
("ALS Chemex"). ALS Chemex is an ISO 9001:2000 certified
laboratory. Pulp and metallics assaying for gold was conducted on
the entire pulverized sample.
As part of its QA/QC program, Nighthawk inserts external gold
standards (low to high grade) and blanks every 20 samples in
addition to the standards, blanks, and pulp duplicates inserted by
ALS Chemex.
About Nighthawk
Nighthawk is a Canadian-based gold
exploration company with 100% ownership of a district-scale land
position within the Indin Lake Greenstone Belt, located
approximately 200 km north of Yellowknife, Northwest Territories, Canada. Nighthawk is
focused on advancing the Colomac Gold Project with a current
inferred resource of 2.613 million ounces of gold (50.305 million
tonnes at an average grade of 1.62 grams per tonne), as well as
advancing its other regional gold deposits and showings within this
largely underexplored Archean gold camp.
The Company has an experienced and dedicated team and is well
funded to complete its goals and objectives over the next 18-24
months.
Neither the Toronto Stock Exchange has neither reviewed nor
accepts responsibility for the adequacy or accuracy of this news
release.
Cautionary Note Regarding Estimates of Resources
Readers are cautioned that mineral resources are not economic
mineral reserves and that the economic viability of resources that
are not mineral reserves has not been demonstrated. The estimate of
mineral resources may be materially affected by geology,
environmental, permitting, legal, title, socio-political, marketing
or other relevant issues. The mineral resource estimate is
classified in accordance with the Canadian Institute of Mining,
Metallurgy and Petroleum's "2014 CIM Definition Standards on
Mineral Resources and Mineral Reserves" incorporated by reference
into NI 43-101. Under Canadian rules, estimates of inferred mineral
resources may not form the basis of feasibility or pre-feasibility
studies or economic studies except for Preliminary Economic
Assessment as defined under NI 43-101. Readers are cautioned not to
assume that further work on the stated resources will lead to
mineral reserves that can be mined economically.
An Inferred Mineral Resource as defined by the CIM Standing
Committee is "that part of a Mineral Resource for which quantity
and grade or quality are estimated on the basis of limited
geological evidence and sampling. Geological evidence is sufficient
to imply but not verify geological and grade or quality continuity.
An Inferred Mineral Resource has a lower level of confidence than
that applying to an Indicated Mineral Resource and must not be
converted to a Mineral Reserve. It is reasonably expected that the
majority of Inferred Mineral Resources could be upgraded to
Indicated Mineral Resources with continued exploration."
Forward-Looking Information
This news release contains "forward-looking information" within
the meaning of applicable Canadian securities legislation.
Forward-looking information includes, but is not limited to,
information with respect to the Company's 2018 drill program
including anticipated metres of drilling and budget, and the timing
and results thereof; an anticipated resource estimate on the Damoti
Lake Gold Deposit, and the timing and results thereof; updated
resource estimate for the Colomac Gold Project, the anticipation of
adding tonnes and ounces, and the possibility of upgrading inferred
ounces to indicated ounces; and any potential development and
production assumptions at Colomac. Generally, forward-looking
information can be identified by the use of forward-looking
terminology such as "plans", "expects", or "does not expect", "is
expected", "budget", "scheduled", "estimates", "forecasts",
"intends", "anticipates", or "does not anticipate", or "believes"
or variations of such words and phrases or state that certain
actions, events or results "may", "could", "would", "might", or
"will be taken", "occur", or "be achieved".
Forward-looking information is based on the opinions and
estimates of management at the date the information is made, and is
based on a number of assumptions and is subject to known and
unknown risks, uncertainties and other factors that may cause the
actual results, level of activity, performance or achievements of
Nighthawk to be materially different from those expressed or
implied by such forward-looking information, including risks
associated with the exploration, development and mining such as
economic factors as they effect exploration, future commodity
prices, changes in foreign exchange and interest rates, actual
results of current exploration activities, government regulation,
political or economic developments, environmental risks, permitting
timelines, capital expenditures, operating or technical
difficulties in connection with development activities, employee
relations, the speculative nature of gold exploration and
development, including the risks of diminishing quantities of
grades of reserves, contests over title to properties, and changes
in project parameters as plans continue to be refined as well as
those risk factors discussed in Nighthawk's annual information form
for the year ended December 31, 2016,
available on www.sedar.com. Although Nighthawk has attempted
to identify important factors that could cause actual results to
differ materially from those contained in 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 information will prove to be accurate, as actual results
and future events could differ materially from those anticipated in
such information. Accordingly, readers should not place undue
reliance on forward-looking information. Nighthawk does not
undertake to update any forward-looking information, except in
accordance with applicable securities laws.
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SOURCE Nighthawk Gold Corp.