Golden Star Resources Announces Mineral Reserves and Resources Estimates as of December 31, 2011
DENVER, CO -- (Marketwire) -- 02/22/12 -- Golden Star Resources Ltd. (NYSE Amex: GSS) (TSX: GSC) (GHANA: GSR) ('Golden Star' or the 'Company') is pleased to announce its Proven and Probable Mineral Reserves (collectively 'Mineral Reserves') and Mineral Resources as at December 31, 2011.
The Mineral Reserve and Mineral Resource estimates have been estimated by our technical personnel in accordance with definitions and guidelines set out in the Definition Standards for Mineral Resources and Mineral Reserves published by the Canadian Institute of Mining, Metallurgy, and Petroleum and as required by Canada's National Instrument 43-101.
MINERAL RESERVES AND MINERAL RESOURCES
The Mineral Reserve and Mineral Resource estimates have been estimated by the Company's technical personnel in accordance with definitions and guidelines set out in the Definition Standards for Mineral Resources and Mineral Reserves published by the Canadian Institute of Mining, Metallurgy, and Petroleum and as required by Canada's National Instrument 43-101.
MINERAL RESERVES
PROVEN & PROBABLE
MINERAL RESERVES As at December 31, 2011 As at December 31, 2010
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Gold Gold
Property Mineral Tonnes Grade Ounces Tonnes Grade Ounces
Reserve Category (millions) (g/t) (millions)(millions) (g/t) (millions)
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Bogoso/Prestea
Total Proven and
Probable
Non-refractory 8.2 2.21 0.58 8.3 2.20 0.59
Refractory 32.6 2.63 2.75 38.9 2.56 3.20
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Total Bogoso/Prestea
Proven and Probable 40.8 2.55 3.34 47.2 2.49 3.78
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Wassa/HBB
------------------------------------------------------
Total Wassa/HBB Proven
and Probable 18.1 1.38 0.80 18.1 1.43 0.83
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Totals
Total Proven and
Probable
Non-refractory 26.3 1.64 1.38 26.4 1.67 1.42
Refractory 32.6 2.63 2.75 38.9 2.56 3.20
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Total Proven and
Probable 58.8 2.19 4.14 65.3 2.20 4.62
Notes to the Mineral Reserve Statement:
(1) The stated Mineral Reserve for Bogoso/Prestea includes Prestea South,
Pampe and Mampon.
(2) The stated Mineral Reserve for Wassa/HBB includes the Hwini-Butre and
Benso properties.
(3) The stated Mineral Reserves have been prepared in accordance with
Canada's National Instrument 43-101 Standards of Disclosure for Mineral
Projects 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 Reserves are equivalent
to Proven and Probable Reserves as defined by the SEC Industry Guide 7.
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.
(4) The 2010 Mineral Reserves were prepared under the supervision of Mr.
Karl Smith, Vice President Technical Services for the Company. Mr. Smith
is a 'Qualified Person' as defined by Canada's National Instrument 43-
101. The 2011 Mineral Reserves were prepared under the supervision of
Dr. Martin Raffield, Senior Vice President Technical Services for the
Company. Dr. Raffield is a 'Qualified Person' as defined by Canada's
National Instrument 43-101.
(5) The Mineral Reserves at December 31, 2011 were estimated using a gold
price of $1,250 per ounce, which is approximately equal to the three-
year average gold price. At December 31, 2010, Mineral Reserves were
estimated using a gold price of $1,025 per ounce.
(6) The terms 'non-refractory' and 'refractory' refer to the metallurgical
characteristics of the ore and are defined in the Glossary of Terms. We
plan to process the refractory ore in our sulfide bio-oxidation plant at
Bogoso and to process the non-refractory ore using our more traditional
gravity, flotation and/or cyanidation techniques.
(7) The slope angles of all pit designs are based on geo-technical 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. The parameters for the pit optimization program
are based on a gold price of $1,250 per ounce, historical and projected
operating costs at Bogoso/Prestea, Wassa and Hwini-Butre and Benso.
Metallurgical recoveries are based on historical performance or
estimated from test work and typically range from 80% to 95% for non-
refractory ores and from 70% to 85% for refractory ores. A government
royalty of 5% is allowed as are other applicable royalties.
(8) Numbers may not add due to rounding.
RECONCILIATION OF MINERAL RESERVES:
Contained Tonnes Ounces
Tonnes Ounces (% of (% of
(millions) (millions) Opening) Opening)
Mineral Reserves at December 31,
2010 65.3 4.62 100% 100%
Gold price increase (1 & 6) 4.5 0.09 7% 2%
Exploration changes (2 & 7) 4.3 0.27 7% 6%
Mining depletion (3) (5.3) (0.38) -8% -8%
Engineering (4) (9.9) (0.46) -15% -10%
---------- ---------- ---------- ----------
Mineral Reserves at December 31,
2011 (5) 58.8 4.14 90% 90%
Notes to the reconciliation of Mineral Reserves:
(1) Gold Price Increase represents changes resulting from an increase in
gold price used in the Mineral Reserve estimates from $1,025 per ounce
in 2010 to $1,250 per ounce in 2011.
(2) Exploration Changes include changes due to geological modeling, data
interpretation and resource block modeling methodology as well as
exploration discovery of new mineralization.
(3) Mining Depletion represents the 2010 Mineral Reserve within the volume
mined in 2011 with adjustments to account for stockpile addition and
depletions during 2011 and therefore does not correspond with 2011
actual gold production.
(4) Engineering includes changes as a result of changes in operating costs,
mining dilution and recovery assumptions, metallurgical recoveries, pit
slope angles and other mine design and permitting considerations.
(5) Numbers may not add due to rounding.
(6) Pit design changes that are primarily due to a higher gold price are
included here.
(7) Pit design changes that are primarily due to exploration discoveries are
included here.
Since the Company reports its Mineral Reserves to both NI 43-101 and SEC Industry Guide 7 standards, it is possible for its Mineral Reserve figures to vary between the two. Where such a variance occurs it will arise from the differing requirements for reporting Mineral Reserves. For example, NI 43-101 has a minimum requirement that Mineral Reserves be supported by a pre-feasibility study, whereas SEC Industry Guide 7 requires support from a detailed feasibility study that demonstrates that economic extraction is justified. For the Mineral Reserves at December 31, 2011, and 2010, there is no difference between the Mineral Reserves as disclosed under NI 43-101 and those disclosed under SEC Industry Guide 7, and therefore no reconciliation is provided.
NON-RESERVE - MEASURED AND INDICATED MINERAL RESOURCES
Cautionary Note to US Investors concerning estimates of Measured and Indicated Mineral Resources
This section uses the terms 'Measured Mineral Resources' and 'Indicated Mineral Resources.' The Company advises US investors that while these terms are recognized and required by Canadian regulations, the US Securities and Exchange Commission does not recognize them. US investors are cautioned not to assume that any part or all of the mineral deposits in these categories will ever be converted intomineral reserves.
The Measured and Indicated Mineral Resources reported below are exclusive of the Proven and Probable Mineral Reserves as shown above and have been estimated in compliance with definitions set out in Canada's National Instrument 43-101.
Except as otherwise provided, the total Measured and Indicated Mineral Resources for all properties have been estimated at an economic cut-off grade based on a gold price of $1,500 per ounce for December 31, 2011 and $1,300 per ounce for December 31, 2010 and on economic parameters deemed realistic. The economic cut-off grades for Mineral Resources are higher than those for Mineral Reserves and are indicative of the fact that the Mineral Resource estimates include material that may become economic under more favorable conditions including increases in gold price.
The following table summarizes Golden Star's estimated non-reserves - Measured and Indicated Mineral Resources as of December 31, 2011 as compared to the totals for December 31, 2010:
Measured & Indicated
Gold
Tonnes Grade
Property (millions) (g/t)
---------- ----------
Bogoso/Prestea 18.4 1.94
Prestea Underground 1.6 12.63
Wassa 14.0 0.99
Benso 2.8 2.54
Chichiwelli Manso 1.4 1.69
Hwini-Butre 1.3 3.02
Father Brown Underground 0.6 5.69
Buesichem Underground 1.2 3.73
---------- ----------
Total 2011 41.3 2.20
Total 2010 54.9 1.99
Notes to the Measured & Indicated Mineral Resources:
(1) The Mineral Resources for Bogoso/Prestea include Pampe and Mampon.
(2) The Mineral Resources were estimated in accordance with the definitions
and requirements of Canada's National Instrument 43-101. The Mineral
Resources are equivalent to Mineralized Material as defined by the SEC
Industry Guide 7.
(3) The Mineral Resources were estimated using optimized pit shells at a
gold price of $1,500 per ounce from which the Mineral Reserves have been
subtracted. Other than gold price, the same optimized pit shell
parameters and modifying factors used to determine the Mineral Reserves
were used to determine the Mineral Resources. In 2010, we used a gold
price of $1,300 per ounce for the optimized shell. The Prestea
Underground resource was estimated using a $1,500 per ounce gold price
and operating cost estimates using an economic gold cut-off of 2.3 g/t.
In 2010, we used a gold price of $1,300 per ounce for the optimized
shell.
(4) The Mineral Resources are not included in and are in addition to the
Mineral Reserves described above.
(5) The Qualified Person reviewing and validating the estimation of the
Mineral Resources is S. Mitchel Wasel, Golden Star Resources Vice
President of Exploration.
(6) Numbers may not add due to rounding.
(7) The Father Brown underground resource has been estimated below the
$1,500 pit shell down to the 750 meters (m) elevation using an economic
gold grade cut-off of 2.2 g/t, which we believe would be the lower cut-
off for underground.
(8) The Buesichem Underground resource has been estimated below the $1,500
pit shell down to 4500m elevation using an economic gold grade cut-off
of 2.8 g/t Au.
(9) The 2010 totals include indicated resources of 2.7 million tonnes at a
grade of 1.75 g/t at the Goulagou property in Burkina Faso. The 2011
totals exclude Goulagou's resources because the Goulagou property was
sold in February 2012.
NON-RESERVES - INFERRED MINERAL RESOURCES
Cautionary Note to US Investors concerning estimates of Inferred Mineral Resources
This section uses the term 'Inferred Mineral Resources.' We advise US investors that while this term is recognized and required by NI 43-101, the US Securities and Exchange Commission 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.
The 2011 Inferred Mineral Resources have been estimated in compliance with definitions defined by NI 43-101.
Tonnes Gold Grade
Property (M) (g/t)
---------- ----------
Bogoso/Prestea 5.1 2.46
Prestea Underground 5.2 7.28
Wassa 0.1 2.03
Benso 0.2 2.61
Hwini-Butre 1.3 1.66
Chichiwelli Manso 0.0 1.98
Father Brown Underground 0.5 5.23
Buesichem Underground 0.8 4.08
---------- ----------
Total 2011 13.3 4.49
Total 2010 16.5 3.66
Notes to Non-Reserves - Inferred Mineral Resources:
(1) The Mineral Resources for Bogoso/Prestea include Pampe and Mampon.
(2) The Mineral Resources were estimated in accordance with the definitions
and requirements of Canada's National Instrument 43-101. The Mineral
Resources are equivalent to Mineralized Material as defined by the SEC
Industry Guide 7.
(3) The Mineral Resources were estimated using optimized pit shells at a
gold price of $1,500 per ounce from which the Mineral Reserves have been
subtracted. Other than gold price, the same optimized pit shell
parameters and modifying factors used to determine the Mineral Reserves
were used to determine the Mineral Resources. In 2010, we used a gold
price of $1,300 per ounce for the optimized shell. The Prestea
Underground resource was estimated using a $1,500 per ounce gold price
and operating cost estimates using an economic gold cut-off of 2.3 g/t.
In 2010, we used a gold price of $1,300 per ounce for the optimized
shell.
(4) The Mineral Resources are not included in and are in addition to the
Mineral Reserves described above.
(5) The Qualified Person reviewing and validating the estimation of the
Mineral Resources is S. Mitchel Wasel, Golden Star Resources Vice
President of Exploration.
(6) Numbers may not add due to rounding.
(7) The Father Brown underground resource has been estimated below the
$1,500 pit shell down to the 750 meters (m) elevation using an economic
gold grade cut-off of 2.2 g/t, which we believe would be the lower cut-
off for underground.
(8) The Buesichem Underground resource has been estimated below the $1,500
pit shell down to 4500m elevation using an economic gold grade cut-off
of 2.8 g/t Au.
(9) The 2010 totals include indicated resources of 2.7 million tonnes at a
grade of 1.75 g/t at the Goulagou property in Burkina Faso. The 2011
totals exclude Goulagou's resources because the Goulagou property was
sold in February 2012.
COMPANY PROFILE
Golden Star holds a 90% equity interest in Golden Star (Bogoso/Prestea) Limited and Golden Star (Wassa) Limited, which respectively own the Bogoso/Prestea and Wassa/HBB open-pit gold mines in Ghana. In addition, Golden Star has an 81% interest in the currently inactive Prestea Underground mine in Ghana, as well as gold exploration interests elsewhere in Ghana, in other parts of West Africa and in Brazil in South America. Golden Star has approximately 259 million shares outstanding.
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. Such statements include our expectations regarding reserves and resources changes for 2012, our 2012 exploration activities and the number of drill rigs conducting such exploration, and our plans for processing refractory ore and non-refractory ore. Investors are cautioned that forward-looking statements are inherently uncertain and involve risks 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 our Form 10-K for 2011. 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.
For further information, please contact:
GOLDEN STAR RESOURCES LTD.
Bruce Higson-Smith
Senior Vice President Finance and Corporate Development
1-800-553-8436
INVESTOR RELATIONS
Jay Pfeiffer
Pfeiffer High Investor Relations, Inc.
303-393-7044