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  • WASSA GOLD MINE, GHANA

    Golden Star Resources is an established gold mining company that holds a 90% interest in the Wassa, Prestea and Bogoso gold mines in Ghana. In 2014, Golden Star produced 261,000 ounces of gold and is expected to produce 250,000 275,000 ounces in 2015. The Company is pursuing brownfield development projects at its Wassa and Prestea mines that are expected to transform these mines into lower cost producers from 2016 onwards.

    The Wassa Gold Mine is located on the eastern flank of the Ashanti belt in Ghana, West-Africa. The mine is located 150 km west of the capital of Accra.

    The Wassa Mine was originally developed as an open-pit heap leach operation with the first material mined in October 1998. Golden Star acquired the Wassa mine in 2002, drilling programs were undertaken shortly after to delineate additional near surface resources. The Wassa Mine has been operating as a conventional open-pit, CIL operation since April 2005, recent deep drilling programs have identified an underground resource which was the subject of a PEA study indicating a positive economic analysis for the underground project and the potential for a combined open pit and underground operation.

    WASSA MINERAL RESOURCES STATEMENT AS OF JULY 31ST, 2014:

    Source

    MEASURED INDICATED INFERRED

    Quantity Grade Metal Quantity Grade Metal Quantity Grade Metal

    kt g/t Au koz Au kt g/t Au koz Au kt g/t Au koz Au

    Wassa OP 25,582 1.41 1,160 237 1.56 12

    Wassa UG 10,116 4.27 1,389 8,841 3.95 1,122

    Total 35,698 2.22 2,549 9,078 3.89 1,134

    GEOLOGY: The Wassa deposit lies within the Ashanti Greenstone Belt along the eastern margin within a volcano-sedimentary assemblage located close to the Tarkwaian basin contact. The lithological sequence is characterized by intercalated meta-mafic volcanic and meta-diorite dykes intercalated with meta-sediments, the sequence is intruded by an Eoeburnean felsic porphyry on the south-western flank of the Wassa mine fold. Mineralization within the Wassa Mine is structurally controlled and related to vein densities and sulphide contents. The mineralization generally consists of broadly tabular zones containing dismembered and folded ribbon-like bodies of narrow quartz vein material. The veins have been folded by four phases of ductile deformation of Eburnean timing.

    DEPOSITS: The Wassa Mine is a unique gold deposit in the Ashanti Belt with gold mineralization interpreted to be of syn-Eoeburnean timing. The deposit has subsequently been affected by multiple phases of Eburnean deformation which resulted in a multi-folded mineralized pattern. Other hydrothermal deposits hosted within the Ashanti belt have been interpreted to be of Eburnean timing, this includes Obuasi, (49.8M Oz) Bogoso-Prestea (17M Oz) and Ahafo (15M Oz). Given the timing of the gold mineralization, Wassa is a potential source for the Tarkwaian paleoplacer deposits.

    Two core boxes displaying lithologies and mineralization style, cross sections, mine geology and regional maps are on display at the PDAC 2015 Convention.

    THE WASSA GOLD MINE HAS BEEN IN OPERATION

    FOR 17 YEARS AND IS EXPECTED TO PRODUCE 105 - 120,000 OUNCES

    OF GOLD IN 2015.

  • BSDD

    332ABSDD306

    BSDD326

    F4 Axial Plane

    F3 Axial Plane

    39500

    39500

    39600

    39600

    39700

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    39800

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    39900

    39900

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    Section 19975Au

    0.01 - 1.001.01 - 5.005.01 - 10.0010.01 - 20.0020.01 - 200.00

    BoreholePit DesignResource shellCurrent SurfaceOriginal TopographyStope

    S1 - BMUS2 - Meta-mafic volcanicS3 - DioriteS4 - MetasedimentsS5 - Felsic prophyryS6 - Meta-mafic volcanic (altered)

    0 100 20050 m

    BSDD

    330

    39600

    39600

    39700

    39700

    39800

    39800

    39900

    39900

    40000

    40000

    40100

    40100

    40200

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    600

    700

    700

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    1100

    0 100 20050 m

    Section 20000

    Au0.01 - 1.00

    1.01 - 5.00

    5.01 - 10.00

    10.01 - 20.00

    20.01 - 200.00

    Borehole

    Pit Design

    Resource shell

    Current Surface

    Original Topography

    High grade ore

    Low grade ore

    Stope

    S20000

    S19975

    S19675

    S19625

    S19500

    S19300

    S19100

    641000

    641000

    642000

    642000

    643000

    643000

    6050

    00

    6050

    00

    6060

    00

    6060

    00

    6070

    00

    6070

    00

    Infrastructure

    S1 - BMUS2 - Metamafic volcanicS3 - Diorite

    S4 - Metasediments

    S5 - Felsic PorphyryS6 - Metamafic volcanic (altered)S7 - Graphitic Mudstone

    WASSAGOLDMINE

    WASSAGOLDMINE

    IvoryCoast

    BurkinaFaso

    Mali

    Ghana Togo

    Benin

    Niger

    0 200 km

    0 20 km

    WASSA GOLD MINE

    Ashanti Complex Cross Section

    0 200 400 m

    Ghana Geology

    West African Craton

    WA S S A G O L D M I N E , G H A N A

    N Y S E M K T : G S S ; T S X : G S C ; G S E : G S R

    WA S S A G O L D M I N E L O C A L G E O L O G Y

    S E C T I O N 1 9 9 7 5 G E O L O G Y S E C T I O N 2 0 0 0 0 M I N E R A L I Z AT I O N