Reserve & Resource Increase

Petra Diamonds Ld
08 October 2007



For release 8 October 2007                                             AIM: PDL


                             Petra Diamonds Limited


         South Africa - substantial increase in Reserves and Resources


Petra Diamonds ('Petra' or 'the Company' or 'the Group') announces an updated
statement of the Group's South African reserves and resources. The statement has
been prepared in accordance with JORC and is in respect of the Koffiefontein,
Helam, Sedibeng and Star mines.


Highlights

  • Updated carat base of 9.33 million carats attributable (11.38 million
    carats gross), an increase of 101% on previous statement (May 2005: 4.64
    million carats attributable)

  • In-situ value of US$1.5 billion attributable (US$1.9 billion gross)

  • JORC compliant attributable reserves increase 66% to 2.95 million carats
    (May 2005: 1.77m carats)

  • JORC compliant attributable resources increase 123% to 6.38 million carats
    (May 2005: 2.86m carats)

  • Increase due to the acquisition of Koffiefontein and additional kimberlite
    fissure units included in the total mineral resource



                 SUMMARY OF ATTRIBUTABLE RESERVES AND RESOURCES

                       COMBINED SOUTH AFRICAN OPERATIONS

                                                      Contained      Contained
                             Tonnes       Grade        Diamonds    Diamonds May
Category                  October 2007 October 2007  October 2007      2005
                           (millions)     (cpht)      (millions)    (millions)
Ore/Diamond reserves
Proven                       18.397        8.3          1.524          0.558
Probable                     1.993         71.3         1.422          1.217
Sub-total                    20.390        14.5         2.946          1.775
Diamond resources
Measured                     40.674        2.9          1.169              -
                                                                          *
Indicated                    12.774        9.5          1.218              -
                                                                          *
Inferred                     31.036        12.9         3.994          2.864
Sub-total                    84.484        7.6          6.381          2.864
Total                       104.874        8.9          9.327          4.639

* Refer to Note 4 below regarding the treatment of measured and indicated
resources of the fissure mines.


The resource statement, in compliance with the AIM Guidance for Mining
Companies, is shown below in total for the Group's South African operations and
then shown split out as to Koffiefontein and the fissure mines (Helam, Sedibeng
and Star combined).  This statement does not include any contribution from
Kimberley Underground which will only form part of Petra's assets when the
conditions in the corresponding acquisition agreement are met.


SUMMARY OF RESERVES AND RESOURCES BY STATUS - COMBINED SOUTH AFRICAN OPERATIONS

Category                       Gross                           Net attributable                Operator

                  Tonnes       Grade     Contained     Tonnes       Grade     Contained
                (millions)     (cpht)     Diamonds   (millions)     (cpht)     Diamonds
                                         (millions)                           (millions)
Ore/Diamond
reserves per
asset

Proven            25.860        7.3        1.886       18.397        8.3        1.524        Refer summaries
                                                                                                       below
Probable           2.105       69.0        1.453        1.993       71.3        1.422        Refer summaries
                                                                                                       below
Sub-total         27.965       11.9        3.339       20.390       14.5        2.946


Diamond
resources per
asset

Measured          58.105        2.9        1.670       40.674        2.9        1.169       Koffiefontein JV

Indicated         18.248        9.5        1.740       12.774        9.5        1.218        Refer summaries
                                                                                                       below
Inferred          43.787       10.6        4.632       31.036       12.9        3.994        Refer summaries
                                                                                                       below
Sub-total         120.140       6.7        8.042       84.484        7.6        6.381

Total             148.105       7.7        11.381      104.874       8.9        9.327




SUMMARY OF RESERVES AND RESOURCES BY STATUS - KOFFIEFONTEIN

Category                       Gross                            Net attributable                Operator

                  Tonnes       Grade      Contained     Tonnes       Grade     Contained
                (millions)     (cpht)     Diamonds    (millions)     (cpht)     Diamonds
                                         (millions)                            (millions)
Ore/Diamond
reserves per
asset

Proven            24.436        4.4         1.080       17.105        4.4        0.756     Koffiefontein JV

Probable            -            -            -            -           -           -

Sub-total         24.436        4.4         1.080       17.105        4.4        0.756


Diamond
resources per
asset

Measured          58.105        2.9         1.670       40.674        2.9        1.169     Koffiefontein JV

Indicated         18.248        9.5         1.740       12.774        9.5        1.218     Koffiefontein JV

Inferred          42.263        4.6         1.960       29.584        4.6        1.372     Koffiefontein JV

Sub-total        118.616        4.5         5.370       83.031        4.5        3.759

Total            143.052        4.5         6.450       100.136       4.5        4.515


Koffiefontein; reserves and resources have been taken from De Beers June 2005
internal scorecard classification (considered to be a conservative
classification) and depleted by mining conducted by De Beers from July 2005 to
March 2006 and by Petra to September 2007. Reserves and resources have been
re-classified in compliance with JORC 2004.


SUMMARY OF RESERVES AND RESOURCES BY STATUS - FISSURE MINES COMBINED (HELAM, SEDIBENG, STAR)

Category                       Gross                            Net attributable                Operator

                  Tonnes       Grade      Contained     Tonnes       Grade     Contained
                (millions)     (cpht)     Diamonds    (millions)     (cpht)     Diamonds
                                         (millions)                            (millions)
Ore/Diamond
reserves per
asset

Proven            1.424        56.6         0.806        1.292       59.5        0.768     Petra/Sedibeng
                                                                                           Mine JV
Probable          2.105        69.0         1.453        1.993       71.3        1.422     Petra/Sedibeng
                                                                                           Mine JV
Sub-total         3.529        64.0         2.259        3.285       66.7        2.190

Diamond
resources per
asset

Measured            -            -            -            -           -           -

Indicated           -            -            -            -           -           -

Inferred          1.524        175.3        2.672        1.452       180.6       2.622     Petra/Sedibeng
                                                                                           Mine JV
Sub-total         1.524        175.3        2.672        1.452       180.6       2.622

Total             5.053        97.6         4.931        4,737       101.6       4.812


Fissure mines; grades and fissure widths are extrapolated downwards below
working levels from detailed historical records collected over many decades of
mining, with confirmation of fissure continuity by diamond drilling where
necessary.



For further information, please contact:
Justine Howarth / Louise Goodeve                 Telephone: [phone]
Parkgreen Communications, London


Adrian Hadden                                    Telephone: [phone]
Collins Stewart, London




Ends


Notes

1. The information in this update that relates to Exploration Results, Mineral
Resources or Ore Reserves is based on information compiled by Jim Davidson, Pr.
Sci Nat (reg No 400031/06), who is a Member of the Geological Society of South
Africa, a 'Recognised Overseas Professional Organisation' ('ROPO'). Jim Davidson
is the Qualified Person for the purposes of the AIM Guidance Note on Mining, Oil
and Gas Companies dated March 2006. Jim Davidson is a full-time employee of the
Company and 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. Jim Davidson has given his written consent to the
inclusion in this announcement of the matters based on his information in the
form and context in which it appears.

2. 'Operator' is name of the company that operates the asset; 'Gross' are 100%
of the reserves and/or resources attributable to the licence whilst 'Net
attributable' are those attributable to the AIM company; 'cpht' is carats per
one hundred tonnes.

3. The previous JORC compliant statement of resources and reserves published by
Petra was dated 26 April 2005. It was prepared by Snowden Mining Industry
Consultants ('Snowden') as part of the documentation required when Petra merged
with Crown Diamonds NL in May 2005. At that time the resources and reserves were
only in respect of the Helam, Sedibeng and Star fissure mines. The current
reserves and resources have been updated using the same parameters applied as
per the Snowden 2005 report.

4. Fissures - measured resources are classified as one level below the base of
the deepest workings, indicated resources as two levels below the base of the
measured resources, and inferred resources as three levels below the base of the
indicated resources. Measured and indicated resources have been converted to
proven and probable reserves by applying historically derived waste rock
dilution and in-stope loss factors to in-situ kimberlite tonnages and grades.
Resources converted to reserves have been subtracted from the overall resource
figure and reported separately. Due to in-stope loss factors of 10% for
shrinkage mining (carried out at Helam and Sedibeng), reserve carats will be
less than resource carats on conversion and this adjustment has been included in
the statements above.



Glossary

'mineral resources' - a concentration or occurrence of material of intrinsic
economic interest in or on the earth's crust in such form, quality and quantity
that there are reasonable prospects for eventual economic extraction.


'inferred mineral resource' - that part of a mineral resource for which tonnage,
grade and mineral content can be estimated with a low level of confidence. It is
inferred from geological evidence and assumed but not verified geologically and/
or through analysis of grade continuity. It is based on information gathered
through appropriate techniques from locations such as outcrops, trenches, pits,
workings and drill holes which may be limited or of uncertain quality and
reliability.


'indicated mineral resource' - that part of a mineral resource for which
tonnage, densities, shape, physical characteristics, grade and mineral content
can be estimated with a reasonable level of confidence. It is based on
exploration, sampling and testing information gathered though appropriate
techniques from locations such as outcrops, trenches, pits, workings and drill
holes. The locations are too widely or inappropriately spaced to confirm
geological and/or grade continuity but are spaced closely enough for continuity
to be assumed.


'measured mineral resource' - that portion of a mineral resource for which
tonnage, densities, shape, physical characteristics, grade and mineral content
can be estimated with a high level of confidence. It is based on detailed and
reliable exploration, sampling and testing information gathered through
appropriate techniques from locations such as outcrops, trenches, pits, workings
and drill holes. The locations are spaced closely enough to confirm geological
and/or grade continuity.


'ore reserves' - those portions of mineral resources which, after the
application of all mining factors, result in an estimated tonnage and grade
which, in the opinion of the competent person making the estimates, can be the
basis of a viable project, after taking account of all relevant modifying
factors.


'probable ore reserve' - the economically mineable part of an indicated, and in
some circumstances measured mineral resource. It includes diluting materials and
allowances for losses which may occur when the material is mined. Appropriate
assessments and studies have been carried out, and include consideration of and
modification by realistically assumed mining, metallurgical, economic,
marketing, legal, environmental, social and governmental factors. These
assessments demonstrate at the time of reporting that extraction could
reasonably be justified.


'proven ore reserve' - the economically mineable part of a measured mineral
resource. It includes diluting material and allowances for losses which may
occur when the material is mined. Appropriate assessments and studies have been
carried out, and include consideration of and modification by realistically
assumed mining, metallurgical, economic, marketing, legal, environmental, social
and governmental factors. These assessments demonstrate at the time of reporting
that extraction could reasonably be justified.


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