redback upgrades resource...again!

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    RBK : Chirano Gold Project - Ghana-Bankable Feasability Update
    ASX Report
    12:14:0223 27/11/2002 Issuer: RBK

    HOMEX - Perth


    * Gold resources increased to 2.05 million ounces (30.4 MT @ 2.1 g/t)
    * Chirano ore reserves to be published in mid December, following
    completion of Bankable Feasibility Study ("BFS")

    * Metallurgical testwork completed confirming amenability of Chirano
    ore to treatment using conventional carbon-in-leach flowsheet

    * Recoveries of 95% achieved from oxide material, 91% from primary
    material and 35-40% by gravity separation

    * BFS geotechnical study confirms no structures affecting pit wall
    stability with average pit wall angles of 58 degrees in primary zone


    Based on results of the 13,633m drilling program at the Chirano Gold
    Project, completed as part of the Bankable Feasibility Study ("BFS")
    during the period May-October 2002, consultants RSG Global Pty Ltd
    ("RSG") has estimated a new Measured, indicated and Inferred Resource
    of 30.4MT grading 2.1g/t for 2,051,000 ounces. This represents a 10%
    increase in the Resources announced in May 2002.

    The new Chirano resource comprises:


    Measured 6,940,000 2.6 562,000
    Indicated 15,150,000 1.9 944,000
    Inferred 8,310,000 2.0 545,000
    TOTAL 30,400,000 2.1 2,051,000

    1. The reported resources are based on a 1 g/t cut off and
    an emulation of 5m x 5m x 5m size blocks

    2. The tonnage has been rounded to the nearest 10,000

    3. All grades have been rounded to the nearest one decimal place

    4. All ounces have been rounded to the nearest 1000

    RSG has subdivided the resource into oxide, transitional and primary
    (fresh or sulphide) with 89% of the resource ounces classified as

    Using a cutoff of 0.8g/t the resources total 37,750,000 tonnes
    grading 1.9g/t for 2,262,000 ounces. Using a 1.2g/t cutoff the
    resources total 24,480,000 tonnes grading 2.3g/t for 1,840,000
    ounces. Ore reserves for Chirano will be published in mid December


    Comprehensive metallurgical testwork undertaken as part of the
    Chirano BFS has also been completed confirming the amenability of
    Chirano ores to a conventional carbon in leach flowsheet. Testwork
    was carried out by Ammtec Limited under the direction of engineering
    consultant Lycopodium Pty Ltd.

    Gold recovery achieved was 95% for oxide ores and 91% for primary and
    transitional ore with typical 35-40% recovery by simple gravity
    separation. Taking into consideration power and capital costs the
    primary ore recovery was optimised on a relatively coarse grind of a
    nominal 106 micron. The reduced grinding requirement will impact
    positively on project capital costs.

    Bond ball mill work indexes for the primary ore are regarded as
    moderate in the range of 12 to 18kwh/t with the project design based
    on 15.9kwh/t. Oxide ore is considerably softer ranging from 3 to
    9kwh/t. Lycopodium has advised that the SAG and ball mills hold under
    option by Red Back (refer ASX announcement 17 October 2002) are
    suitable for milling of Chirano ore.

    Testwork has also confirmed that the ore exhibits low reagent
    consumptions with a total cyanide consumption of 0.5kg/t and lime

    These results are considered excellent and confirm results obtained
    from the earlier testwork.


    BFP Consultants Pty Ltd ("BFP") has completed an assessment of
    geotechnical aspects of the proposed Chirano open pit mine
    development based on the recently completed BFS diamond drilling.

    BFP conclude that Chirano rocks are generally strong and of good
    quality and that the geotechnical features appear consistent
    throughout the area examined. No major structures detrimental to
    overall pit wall stability were observed.

    BFP recommends 70 degree open pit wall batter angles in primary rock
    with 45 degree lay backs in weathered material. Berms should be 5m
    wide and spaced 20m apart. This translates to an overall pit wall
    slope angle of 58 degrees in fresh rock and 40 degrees in the
    weathered profile.

    Application of the steep BFP parameters to the pit designs will
    minimise strip ratios and maximise the economic recovery of gold from
    the pits.

    R Ashton


    The resource estimate for the Chirano Project has been categorised
    based on the September 1999 edition of the Australasian Code for
    Reporting of Mineral Resources and Ore Reserves (The JORC Code). The
    resource estimation study has been carried out jointly by Brett
    Gossage, Manager of Resources at RSG Global, and James Ridley, a
    Senior Geologist with RSG Global, who are both Corporate Members of
    the Australian Institution of Mining and Metallurgy, and are defined
    as "Competent Persons", as detailed in the JORC Code. Mr Gossage and
    Mr Ridley consent to the inclusion in this report of the resource
    data in the form in which it appears

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