TORONTO, March 28, 2019 /CNW/ - Golden Star
Resources Ltd. (NYSE American: GSS; TSX: GSC; GSE:
GSR) ("Golden Star" or the "Company") announces its
Mineral Reserves and Mineral Resources estimate as of December 31, 2018 with a 6% increase in total
Mineral Reserves after depletion, including a 47% increase in Wassa
Underground Gold Mine ("Wassa Underground") Mineral Reserves.
Highlights
- Proven and Probable Mineral Reserves increased by 6% to 1.8
million ounces of gold after mined depletion
- Measured and Indicated Mineral Resources stable at 5.9 million
ounces of gold
- Inferred Mineral Resources increased by 12% to 7.2 million
ounces of gold
- Wassa Underground Mineral Reserve increased by 47% after mined
depletion
- Prestea Mineral Reserve decreased by 36% including mined
depletion
Sam Coetzer, President and
Chief Executive Officer of Golden
Star, commented:
"The updated Mineral Reserve at Wassa Underground shows a
significant increase, specifically in the upper levels of the mine,
and strongly suggests that there is excellent potential to increase
our production rate in the near term. In addition, the increase of
over 1 million ounces of gold in Inferred Mineral Resources at the
Wassa complex to over 6.4 million ounces of gold further
demonstrates the potential for the mine. The Company continues to
improve its view of the orebody and I am very excited by how Wassa
Underground is turning into a world class mine.
"At Prestea, the mine is endowed with good infrastructure and
the focus remains on improving operations. The Company continues to
address the ramp up challenges with the Alimak shrinkage mining
method, and expects steady productivity improvements this year from
the mine."
MINERAL RESERVES AND MINERAL RESOURCES SUMMARY
The following table provides a summary of Golden Star's estimated Proven and Probable
Mineral Reserves, Measured and Indicated Mineral Resources and
Inferred Mineral Resources as of December
31, 2018:
|
Tonnes
('000)
|
Grade
(g/t
Au)
|
Gold
Content
('000 oz)
|
Proven and
Probable Mineral Reserves1
|
19,596
|
2.84
|
1,790
|
Measured and
Indicated Mineral Resources1,2
|
66,814
|
2.77
|
5,952
|
Inferred Mineral
Resources1
|
57,333
|
3.92
|
7,224
|
|
|
Notes to
Table:
|
1
|
Includes
non-refractory material only
|
2
|
Mineral Resources are
inclusive of Mineral Reserves
|
Mineral Reserves were estimated using a gold price of
$1,250 per ounce. Mineral Resources
were estimated using a gold price of $1,450 per ounce.
MINERAL RESERVE ESTIMATE: BREAKDOWN BY ASSET
During 2018, Golden Star's Proven
and Probable Mineral Reserves increased by 97,000 ounces, primarily
as a result of positive conversion of Mineral Resources at Wassa
Underground.
The following table provides a breakdown of Golden Star's estimated Proven and Probable
Mineral Reserves as of the dates set forth therein:
Mineral
Reserves
|
Dec 31,
2018
|
Dec 31,
2018
|
Dec 31,
2018
|
Dec 31,
2017
|
Proven Mineral
Reserve
|
Probable
Mineral
Reserve
|
Proven and
Probable
Mineral Reserve
|
Proven and
Probable
Mineral Reserve
|
tonnes
|
grade
|
ounces
|
tonnes
|
grade
|
ounces
|
tonnes
|
grade
|
ounces
|
tonnes
|
grade
|
ounces
|
(000)
|
g/t Au
|
(000)
|
(000)
|
g/t Au
|
(000)
|
(000)
|
g/t Au
|
(000)
|
(000)
|
g/t Au
|
(000)
|
Wassa Open
Pit
|
-
|
-
|
-
|
9,920
|
1.57
|
500
|
9,920
|
1.57
|
500
|
12,254
|
1.30
|
512
|
Wassa
Underground
|
834
|
4.55
|
122
|
6,647
|
3.87
|
827
|
7,481
|
3.95
|
949
|
4,899
|
4.11
|
647
|
Stockpiles
|
1,205
|
0.63
|
24
|
-
|
-
|
-
|
1,205
|
0.63
|
24
|
1,595
|
0.71
|
37
|
Subtotal
Wassa
|
2,039
|
2.23
|
146
|
16,567
|
2.49
|
1,327
|
18,606
|
2.46
|
1,473
|
18,748
|
1.98
|
1,196
|
Mampon
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
105
|
2.23
|
8
|
Prestea
South
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
103
|
1.80
|
6
|
Prestea
Underground
|
37
|
9.07
|
11
|
789
|
12.04
|
305
|
826
|
11.91
|
316
|
1,165
|
12.35
|
463
|
Stockpiles
|
27
|
1.18
|
1
|
-
|
-
|
-
|
27
|
1.18
|
1
|
547
|
1.21
|
21
|
Subtotal
Prestea
|
64
|
5.74
|
12
|
789
|
12.04
|
305
|
853
|
11.57
|
317
|
1,920
|
8.06
|
497
|
GSR
Total
|
2,103
|
2.34
|
158
|
17,356
|
2.93
|
1,632
|
19,459
|
2.86
|
1,790
|
20,668
|
2.55
|
1,693
|
Notes to the Mineral Reserve Estimate:
- The stated Mineral Reserves comply with the requirements of
National Instrument 43-101 – Standards of Disclosure for Mineral
Projects ("NI 43-101") and are classified in accordance with the
Canadian Institute of Mining, Metallurgy and Petroleum's "CIM
Definition Standards – For Mineral Resources and Mineral Reserves".
Mineral Reserve estimates reflect the Company's reasonable
expectation that all necessary permits and approvals will be
obtained and maintained. Mining dilution and mining recovery vary
by deposit and have been applied in estimating the Mineral
Reserves.
- Mineral Reserves are the economic portion of the Measured and
Indicated Mineral Resources. Mineral Reserve estimates include
mining dilution at grades assumed to be zero.
- The 2018 Mineral Reserves were prepared under the supervision
of Dr. Martin Raffield, Executive
Vice President and Chief Technical Officer for the Company. Dr.
Raffield is a QP as defined by NI 43-101.
- The Mineral Reserves at December 31,
2018 were estimated using a gold price assumption of
$1,250 per ounce.
- The slope angles of all pit designs are based on geotechnical
criteria as established by external consultants. The size and shape
of the pit designs are guided by consideration of the results from
a pit optimization program.
- Cut-off grades have been estimated based on operating cost
projections, mining dilution and recovery, royalty and stream
payment requirements and applicable metallurgical recovery.
- Marginal cut-off grade estimate for the Wassa open pit is 0.7
grams per tonne ("g/t") of gold ("Au").
- Break-even cut-off grade estimates for the underground mines
are as follows: Wassa Underground 2.4 g/t Au; and the Prestea
Underground Gold Mine ("Prestea Underground") 7.0 g/t Au.
- Prestea Underground Proven Mineral Reserve includes underground
broken stocks.
- Numbers may not add due to rounding.
- Only non-refractory material is included in Mineral
Reserves.
Reconciliation of Mineral Reserves
Figure 1 provides a reconciliation of the Company's Proven and
Probable Mineral Reserves from December 31,
2017 to December 31, 2018.
WASSA MINERAL RESERVE
The total Wassa Mineral Reserve has increased by 23% after 2018
mining depletion. This increase is attributable to strong results
from the 2018 underground definition drilling program combined with
a stope design optimization process. Drilling from surface has
extended the Indicated Mineral Resource approximately 65 metres
("m") to the south and a hanging wall drive has allowed the
definition drilling to access areas to the south of the current
stoping area.
Open pit Mineral Reserve tonnes have reduced by 20% and the
grade has increased by 20% resulting in equivalent ounces. This
change is as a result of increasing the marginal cut-off grade from
0.6g/t in 2017 to 0.7g/t in 2018 to account for a royalty payment
that was omitted in 2017. The Mineral Reserve ounces have remained
the same due to an increase in the rock density estimate following
extensive testing and changes in the resource model.
PRESTEA MINERAL RESERVE
At Prestea the open pit Mineral Reserve was depleted in 2018 and
additional material was mined during the year that was outside of
the reserve estimate.
The underground Mineral Reserve has reduced by 146,000 ounces as
a result of 2018 mining depletion and changes to the resource model
following definition drilling and underground development. The new
interpretation of the resource includes areas defined by drilling
and raising where fault movement has resulted in areas of ore loss
within the planned stopes.
The interpretation of the plunge of the high grade core of the
resource has moved to the north of the current stoping area. This
has resulted in loss of Mineral Reserves between 24 and 27L.
Exploration drilling is currently being carried out in this
northern area, both above and below 24L, and the expectation is to
be able to identify additional Mineral Resources during 2019 to
replace these losses.
MEASURED AND INDICATED MINERAL RESOURCES: BREAKDOWN BY
ASSET
Golden Star's Mineral Resources
at its two assets, Wassa and Prestea, decreased slightly in
2018.
The following table provides a breakdown of Golden Star's estimated Measured and Indicated
Mineral Resources as of the dates set forth therein:
Measured
and
Indicated
Mineral
Resources
|
Dec 31,
2018
|
Dec 31,
2018
|
Dec 31,
2018
|
Dec 31,
2017
|
Measured
Mineral
Resources
|
Indicated
Mineral
Resources
|
Measured and
Indicated
Mineral Resources
|
Measured and
Indicated
Mineral Resources
|
tonnes
|
grade
|
ounces
|
tonnes
|
grade
|
ounces
|
tonnes
|
grade
|
ounces
|
tonnes
|
grade
|
ounces
|
(000)
|
g/t Au
|
(000)
|
(000)
|
g/t Au
|
(000)
|
(000)
|
g/t Au
|
(000)
|
(000)
|
g/t Au
|
(000)
|
Wassa Open
Pit
|
0
|
0.00
|
0
|
28,042
|
1.39
|
1,254
|
28,042
|
1.39
|
1,254
|
26,652
|
1.32
|
1,134
|
Wassa
Underground
|
593
|
5.66
|
108
|
11,914
|
4.21
|
1,613
|
12,507
|
4.28
|
1,721
|
13,003
|
4.10
|
1,713
|
Father Brown Adoikrom
UG
|
0
|
0
|
0
|
981
|
7.54
|
238
|
981
|
7.54
|
238
|
1,242
|
5.84
|
233
|
Wassa
Other
|
0
|
0
|
0
|
2,308
|
2.36
|
175
|
2,308
|
2.36
|
175
|
2,997
|
2.52
|
243
|
Subtotal
Wassa
|
593
|
5.66
|
108
|
43,246
|
2.36
|
3,281
|
43,839
|
2.40
|
3,388
|
43,894
|
2.35
|
3,323
|
Bogoso/Prestea
Refractory
|
0
|
0
|
0
|
17,677
|
2.85
|
1,619
|
17,677
|
2.85
|
1,619
|
17,809
|
2.84
|
1,625
|
Mampon
|
0
|
0
|
0
|
83
|
1.71
|
5
|
83
|
1.71
|
5
|
103
|
1.59
|
5
|
Prestea
South
|
0
|
0
|
0
|
1,521
|
2.15
|
105
|
1,521
|
2.15
|
105
|
1,627
|
2.12
|
111
|
Prestea
Underground
|
9
|
30.07
|
9
|
1,298
|
16.73
|
698
|
1,308
|
16.82
|
707
|
1,649
|
15.16
|
804
|
Bogoso/Prestea
Other
|
0
|
0
|
0
|
2,387
|
1.66
|
128
|
2,387
|
1.66
|
128
|
2,414
|
1.65
|
128
|
Subtotal
Bogoso/Prestea
|
9
|
30.07
|
9
|
22,966
|
3.46
|
2,555
|
22,975
|
3.47
|
2,564
|
23,601
|
3.52
|
2,673
|
Total
|
602
|
6.03
|
117
|
66,212
|
2.74
|
5,836
|
66,814
|
2.77
|
5,952
|
67,495
|
2.76
|
5,996
|
TOTAL NON
REFRACTORY
|
602
|
6.03
|
117
|
48,535
|
2.7
|
4,216
|
49,137
|
2.74
|
4,333
|
49,686
|
2.74
|
4,371
|
INFERRED MINERAL RESOURCES: BREAKDOWN BY ASSET
Golden Star's Inferred Mineral
Resources increased by 13% to 7.2 million ounces during 2018, with
the increase delivered primarily at Wassa through step out drilling
with additional contributions from Father Brown, as was previously
reported on February 19, 2019.
The following table provides a breakdown of Golden Star's estimated Inferred Mineral
Resources as of the dates set forth below:
|
December 31,
2018
Inferred Mineral
Resources
|
April 13,
2018
Inferred Mineral
Resources
|
tonnes
(000)
|
grade
g/t Au
|
ounces
(000)
|
tonnes
(000)
|
grade
g/t Au
|
ounces
(000)
|
Wassa Open
Pit
|
23
|
0.74
|
1
|
91
|
1.16
|
3
|
Wassa
Underground
|
50,661
|
3.65
|
5,945
|
44,909
|
3.57
|
5,153
|
Father Brown Adoikrom
UG
|
2,313
|
6.38
|
475
|
1,506
|
5.08
|
246
|
Wassa
Other
|
382
|
2.10
|
26
|
402
|
1.86
|
24
|
Subtotal
Wassa
|
53,379
|
3.76
|
6,446
|
46,908
|
3.60
|
5,426
|
Mampon
|
14
|
1.68
|
1
|
14
|
1.68
|
1
|
Prestea
South
|
68
|
1.89
|
4
|
68
|
1.89
|
4
|
Prestea
Underground
|
2488
|
8.42
|
674
|
3,193
|
8.46
|
868
|
Bogoso/Prestea
Others
|
468
|
1.50
|
23
|
470
|
1.50
|
23
|
Subtotal
Bogoso/Prestea
|
3,038
|
7.18
|
701
|
3,745
|
7.44
|
896
|
Bogoso/Prestea
Refractory
|
916
|
2.61
|
77
|
922
|
2.60
|
77
|
Total (including
refractory)
|
57,333
|
3.92
|
7,224
|
51,574
|
3.86
|
6,399
|
TOTAL
NON-REFRACTORY
|
56,417
|
3.94
|
7,147
|
50,653
|
3.88
|
6,322
|
|
|
Notes to Mineral
Resource Estimates
|
1
|
The Mineral Resources
for "Bogoso/Prestea Others" include Chujah, Dumasi, Bogoso North,
Buesichem, Opon
and Ablifa
|
2
|
The Wassa Underground
Mineral Resource has been estimated below the $1,450 per ounce of
gold pit shell
using an economic gold grade cut-off of 2.1 g/t Au, which the
Company believes would be the lower cut-off
grade for underground mining and constrained to a 0.4 g/t Au
mineralized grade shell
|
3
|
The Father Brown
Underground Mineral Resource has been estimated below the $1,450
per ounce of gold pit
shell using an economic gold grade cut-off of 3.2 g/t Au, which the
Company believes would be the lower cut-off
grade for underground mining
|
4
|
Prestea Underground
Mineral Resource has been estimated below the $1,450 per ounce pit
shell of Prestea
South down to 3,800 metres elevation using a gold cut-off grade at
6.1 g/t Au
|
5
|
Mineral Resources
were estimated using optimized pit shells at a gold price of $1,450
per ounce. Other than
gold price, the same optimized pit shell and underground parameters
and modifying factors used to determine the
Mineral Reserves were used to determine the Mineral
Resources
|
6
|
Mineral Resources are
inclusive of Mineral Reserves
|
7
|
Numbers may not add
correctly due to rounding
|
All monetary amounts refer to United States dollars
unless otherwise indicated.
Company Profile
Golden Star is an established
gold mining company that owns and operates the Wassa and Prestea
underground mines in Ghana,
West Africa. Listed on the NYSE
American, the Toronto Stock Exchange and the Ghana Stock Exchange,
Golden Star is focused on delivering
strong margins and free cash flow from its two high-grade, low cost
underground mines. Gold production guidance for 2019 is
220,000–240,000 ounces at a cash operating cost per
ounce1 of $620–$680. As the winner of the PDAC 2018
Environmental and Social Responsibility Award, Golden Star is committed to leaving a positive
and sustainable legacy in its areas of operation.
Notes
1. See
"Non-GAAP Financial Measures".
Statements Regarding Forward-Looking Information
Some statements contained in this news release are
"forward-looking statements" within the meaning of the Private
Securities Litigation Reform Act of 1995 and "forward looking
information" within the meaning of Canadian securities laws.
Forward looking statements and information include but are not
limited to, statements and information regarding: the potential to
increase production rate of Wassa Underground in the near term due
to increased Mineral Reserves in the upper levels of the mine, the
expectation of steady productivity improvements in 2019 at Prestea,
the expectation of being able to identify additional Mineral
Resources at Prestea during 2019 to replace losses, the selection
of lower cut-off grades for underground mining at Wassa Underground
and Father Brown Underground, and 2019 production guidance and cash
operating cost per ounce guidance. Generally, forward-looking
information and statements can be identified by the use of
forward-looking terminology such as "plans", "expects", "is
expected", "budget", "scheduled", "estimates", "forecasts",
"intends", "anticipates", "believes" or variations of such words
and phrases (including negative or grammatical variations) or
statements that certain actions, events or results "may", "could",
"would", "might" or "will be taken", "occur" or "be achieved" or
the negative connotation thereof. Investors are cautioned that
forward-looking statements and information are inherently uncertain
and involve risks, assumptions and uncertainties that could cause
actual facts to differ materially. There can be no assurance that
future developments affecting the Company will be those anticipated
by management. Please refer to the discussion of these and other
factors in Management's Discussion and Analysis of financial
conditions and results of operations for the year ended
December 31, 2018. Additional and/or
updated factors will be included in our annual information form for
the year ended December 31, 2018
which will be filed on SEDAR at www.sedar.com. The forecasts
contained in this press release constitute management's current
estimates, as of the date of this press release, with respect to
the matters covered thereby. We expect that these estimates will
change as new information is received. While we may elect to update
these estimates at any time, we do not undertake any estimate at
any particular time or in response to any particular event.
Non-GAAP Financial Measures
In this press release, we use the term "cash operating cost per
ounce". This term should be considered as Non-GAAP Financial
Measures as defined in applicable Canadian and United States securities laws and should not
be considered in isolation or as a substitute for measures of
performance prepared in accordance with International Financial
Reporting Standards ("IFRS"). "Cash operating cost per ounce" for a
period is equal to the cost of sales excluding depreciation and
amortization for the period less royalties, the cash component of
metals inventory net realizable value adjustments and severance
charges divided by the number of ounces of gold sold (excluding
pre-commercial production ounces) during the period. This measure
is not representative of all cash expenditures as it does not
include income tax payments or interest costs. Changes in numerous
factors including, but not limited to, mining rates, milling rates,
gold grade, gold recovery, and the costs of labor, consumables and
mine site general and administrative activities can cause this
measure to increase or decrease. We believe that this measure is
the same or similar to the measures of other gold mining companies,
but may not be comparable to similarly titled measures in every
instance. Please see our "Management's Discussion and Analysis of
Financial Condition and Results of Operations for the year ended
December 31, 2018" for a
reconciliation of this Non-GAAP Financial Measures to the nearest
IFRS measure.
Technical Information
The Mineral Reserve and Mineral Resource estimates have been
compiled by the Company's technical personnel in accordance with
definitions and guidelines set out in the Definition Standards for
Mineral Resources and Mineral Reserves adopted by the Canadian
Institute of Mining, Metallurgy, and Petroleum and as required
by Canada's National Instrument 43-101 – Standards of
Disclosure for Mineral Projects ("NI 43-101"). Mineral Reserve
estimates reflect the Company's reasonable expectation that all
necessary permits and approvals will be obtained and maintained.
Mining dilution and mining recovery vary by deposit and have been
applied in estimating the Mineral Reserves.
The Mineral Resource technical contents of this press release
have been reviewed and approved by S. Mitchel Wasel, BSc Geology, a
"Qualified Person" pursuant to NI 43-101. Mr. Wasel is Vice
President Exploration for Golden
Star and an active member of the Australasian Institute
of Mining and Metallurgy. The 2017 and 2016 estimates of Mineral
Resources were prepared under the supervision of Mr. Wasel. The
Mineral Reserve technical contents of this press release, and the
2017 and 2016 estimates of Mineral Reserves, have been reviewed and
approved by and were prepared under the supervision of Dr.
Martin Raffield, Senior Vice
President, Project Development and Technical Services for the
Company. Dr. Raffield is a "Qualified Person" as defined by NI
43-101.
Additional scientific and technical information relating to the
mineral properties referenced in this news release are contained in
the following current technical reports for those properties
available at www.sedar.com: (i) Wassa - "NI 43-101
Technical Report on a Feasibility Study of the Wassa Open Pit Mine
and Underground Project in Ghana"
effective date December 31, 2014;
(ii) Prestea Underground - "NI 43-101 Technical Report on a
Feasibility Study of the Prestea Underground Gold Project in
Ghana" effective date November 3, 2015; and (iii) Bogoso - "NI
43-101 Technical Report on Resources and Reserves Golden Star
Resources Ltd., Bogoso Prestea Gold Mine, Ghana" effective date December 31, 2013.
Cautionary Note to US Investors Concerning Estimates of
Measured and Indicated Mineral Resources
This press release uses the terms "Measured Mineral Resources"
and "Indicated Mineral Resources". The Company advises US investors
that while these terms are recognized and required by NI 43-101,
the US Securities and Exchange Commission ("SEC") does
not recognize them. Also, disclosure of contained ounces is
permitted under Canadian regulations; however
the SEC generally requires Mineral Resource information
to be reported as in-place tonnage and grade. US Investors are
cautioned not to assume that any part or all of the mineral
deposits in these categories will ever be converted into Mineral
Reserves.
Cautionary Note to US Investors Concerning Estimates of
Inferred Mineral Resources
This press release uses the term "Inferred Mineral Resources".
The Company advises US investors that while this term is recognized
and required by NI 43-101, the SEC does not recognize it.
"Inferred Mineral Resources" have a great amount of uncertainty as
to their existence, and great uncertainty as to their economic and
legal feasibility. It cannot be assumed that all or any part of
Inferred Mineral Resources will ever be upgraded to a higher
category. In accordance with Canadian rules, estimates of Inferred
Mineral Resources cannot form the basis of feasibility or other
economic studies. US investors are cautioned not to assume that any
part or all of the Inferred Mineral Resource exists, or is
economically or legally mineable.
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multimedia:http://www.prnewswire.com/news-releases/golden-star-announces-mineral-reserve-and-mineral-resource-update-wassa-underground-reserves-increase-47-300819900.html
SOURCE Golden Star Resources Ltd.