2010 Annual Report - Grange Resources

DECEMBER 2010 ANNUAL REPORT 17
Mineral Resources and Ore Reserves
Savage River Operations
The following tables show the Mineral Resources and Ore Reserves for the Savage River
operations as at 31 May 2010. These include the addition of new ore lenses in the North
Pit and the depletion as a result of mining that occurred during the year. Mineral
Resources and Ore Reserves are categorised in accordance with the Australasian Code
for Reporting of Mineral Resources and Ore Reserves (JORC Code, 2004). Estimated
Measured and Indicated Mineral Resources include those Mineral Resources modified to
produce the estimated Ore Reserves. Mineral Resources which are not included in the
Ore Reserves did not meet the required economic viability hurdle at the time of last
review.
Mineral Resources
A summary of the total Mineral Resources for Savage River as at 31 May 2010
is as follows:
2010 2009
Tonnes Grade Tonnes Grade
Mineral Resources (million) (%DTR) (million) (%DTR)
Measured 86.4 54 88.0 53
Indicated 131.9 53 136.0 52
Inferred 87.8 49 92.2 47
Total 306.1 52 316.2 51
Ore Reserve
A summary of the ore reserve for Savage River as at 31 May 2010 is as follows:
2010 2009
Tonnes Grade Tonnes Grade
Ore Reserves (million) (%DTR) (million) (%DTR)
Proved 50.6 51 52.4 50
Probable 67.9 51 72.0 49
Total 118.5 51 124.4 49
The information in this release that relates to Exploration Results or Mineral Resources in
relation to the Savage River Project is based on information compiled by Mr Ben
Maynard, who is a Member of the Australasian Institute of Mining and Metallurgy and is a
full time employee of Grange Resources Limited. Mr Maynard has sufficient experience
which is relevant to the style of mineralisation and type of deposit under consideration
and to the activity which he is undertaking to qualify as a Competent Person as defined
in the 2004 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral
Resources and Ore Reserves’. Mr Maynard consents to the inclusion in the release of
the matters based on his information in the form and context in which it appears.
The classification of Mineral Resources
was considered appropriate on the basis
of drill hole spacing, sample interval,
geological interpretation and
representativeness of assay data and was
based on a number of factors:
◆ ◆ A lower cut-off grade of 15% DTR
was used in the calculation of both the
Mineral Resources and Ore Reserves
◆ ◆ The estimation was constrained within
the interpreted geological domain
◆ ◆ The Ordinary Kriging and Inverse
Distance interpolation methods were
carried out on drilling data composited
to 2 metres
◆ ◆ Oxidised material was not included in
this statement of Mineral Resources
◆ ◆ Tonnages were estimated on a dry
basis
◆ ◆ Bulk density for samples taken from
diamond drill core has been physically
determined by the weight-in-air/
weight-in-water method. Samples are
unsealed during this process as most
material is competent and/or of low
porosity
◆ ◆ The Ore Reserve was calculated using
a 1.087 dilution factor and a mining
recovery factor of 0.939. These factors
are based on periodic reconciliation
specific to mining areas
◆ ◆ The survey surface used for reporting
North Pit was the end-of-month May
2010 surface.
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