Additional iron ore resources

Rio Tinto PLC
07 February 2008


Rio Tinto reports three billion tonnes of additional iron ore Resources


7 February 2008


Rio Tinto has further strengthened its leading position in the Pilbara with a
3.0 billion tonne addition to its iron ore Resource base.


This came through the discovery of a major new Resource at Caliwingina, and
significant improvement in confidence of resources associated with known
deposits.


The Chief Executive of Rio Tinto Iron Ore, Sam Walsh, said significant technical
and study work has led to increased confidence in Rio Tinto's position in the
Pilbara.


'Rio Tinto occupies the largest mineralisation and land position in the Pilbara,
one of the world's great iron ore producing regions. This advantage is
strengthened by addition of the newly discovered Resource at Caliwingina,
comprising 875 million tonnes of iron ore only 15 kilometres from our railway
and only 150 km from our ports at Dampier and Cape Lambert, as well as
significant additions around known deposits.'


Mineral Resource Additions


1.    Addition of Caliwingina


The newly discovered Caliwingina Resource is within the Mt Pyrton Project area
which lies 100 km north northwest of Tom Price and is approximately 15 km from
the Rio Tinto Iron Ore Tom Price to Dampier railway line.


The Resource is situated within the Late Archaean to Early Proterozoic
(2765-2470 Ma) Hamersley Basin. The Lower Hamersley Group rocks within this area
form rounded outcrops on the edge of the Fortescue River basin with the Upper
Hamersley Group rocks forming larger steeper hills behind. Lithologies comprise
meta-sedimentary rocks from the Hamersley Group and cover units of the Tertiary
and Quaternary.


Rio Tinto initially conducted exploration for Channel Iron Deposit (CID) in the
southern part of Caliwingina using geophysical techniques and an extensive
reverse circulation (RC) drilling programme during 2002-2003 which delineated a
6 km continuous length of CID. During 2005/2006 Rio Tinto continued an RC
drilling programme to the north following the CID channel to the out wash area
in the Fortescue Valley.


The Caliwingina North area now has sufficient drilling coverage (173 RC holes
for 11,503 metres on a nominal 500 by 200 metre grid spacing) to define an
Inferred CID Mineral Resource. All drilling was sampled at two metre intervals
using appropriate Standard and Duplicate check sample methods, followed by QA/QC
analysis. A 3D geological block model of the domains, including the CID, within
the channel was built using 100m by 100m by 2m blocks followed by grade
estimation using Inverse Distance.


Caliwingina North CID Deposit Inferred Mineral Resources (for Fe >55%).

Caliwingina North         Tonnes (Mt)       Fe %                  Density

Total                      875 Mt           56.9                    2.6


Drill evaluation work will continue in the Caliwingina Prospect during 2008/09
to update the resource base. Also diamond drilling will be conducted to improve
grade estimation confidence as well as for Metallurgical and density test-work.


2.      Reporting of Brockman Process Ore


Brockman Process Ore is being reported here for the first time (apart from Tom
Price). The additional resource is contained within the mineralisation envelope
that also defines the high grade (HG) for 15 known deposits. Only bedded Dales
Gorge (DG1 to DG3), Joffre (J1 to J6) and footwall zone Process Ore is reported.
All Process Ore is reported as in-situ tonnes and grade. The newly reported
Resource only requires application of standard processing technology to be won
from material that will be extracted according to the long term mining schedule.


Undeveloped Brockman Process Ore (>or=50% Fe <60% Fe and >or=3% Al2O3
<6% Al2O3).


Brockman Un-Developed Process Ore                 Tonnes (Mt)                    Fe %

Measured                                              220                        57.6
Indicated                                             460                        57.5
Inferred                                             1,105                       54.4
Total                                                1,785                       55.6


Reported Brockman Deposits incorporating Brockman Process Ore are:


  • B1 Deposit
  • B26 Deposit
  • Brockman 2
  • Brockman 4
  • Channar
  • Eastern Range
  • Giles Mini
  • Koodaideri
  • Paraburdoo Brockman Deposits
  • Paraburdoo Western Range
  • Rhodes Ridge Central
  • Section 10
  • Section 17
  • Texas
  • Turee Syncline



3.      Increase in the Hope 4 Resource base


Re-estimation work on Hope 4 during 2007 has added an additional 290 Mt of
Resource.


  • Hope Downs 4 has added an additional 95 Mt of HG (reported in a separated
    release in December 2007)
      • (Fe >or=60% Fe)

Hope Downs 4 High Grade                            Tonnes (Mt)                    Fe %

Indicated                                              100                        62.3
Inferred                                               205                        62.4
Total                                                  305                        62.4



  • 195 Mt of Brockman Process Ore for Hope Downs 4.
      • (>or=50% Fe <60% Fe and >or=3% Al2O3 <6% Al2O3)

Hope Downs 4 Process Ore                           Tonnes (Mt)                    Fe %

Indicated                                              80                         56.4
Inferred                                               115                        57.1
Total                                                  195                        56.8



The information in this report that relates to Mineral Resources is based on
information compiled by John Phillips who is a member of the Australasian
Institute of Mining and Metallurgy. John Phillips is a full-time employee of Rio
Tinto Iron Ore and has experience which is relevant to the style of
mineralisation and type of deposits under consideration and to the activity
which they have undertaken to qualify as a Competent Person as defined in the
2004 Edition of the 'Australasian Code for Reporting of Exploration Results,
Minerals Resources and Ore Reserves'.  John Phillips consents to the inclusion
in the report of the matters based on their information in the form and context
in which it appears.

As required by the Australian Stock Exchange, the information presented here
contain details of other mineralisation that has a reasonable prospect of being
economically extracted in the future but which is not yet classified as Proved
or Probable Reserves.  This material is defined as Mineral Resources under the
JORC Code.  Estimates of such material are based largely on geological
information with only preliminary consideration of mining, economic and other
factors.  While in the judgement of the Competent Person there are realistic
expectations that all or part of the Mineral Resources will eventually become
Proved or Probable Reserves, there is no guarantee that this will occur as the
result depends on further technical and economic studies and prevailing economic
conditions in the future.


About Rio Tinto


Rio Tinto is a leading international mining group headquartered in the UK,
combining Rio Tinto plc, a London listed company, and Rio Tinto Limited, which
is listed on the Australian Securities Exchange.



Rio Tinto's business is finding, mining, and processing mineral resources. Major
products are aluminium, copper, diamonds, energy (coal and uranium), gold,
industrial minerals (borax, titanium dioxide, salt, talc) and iron ore.
Activities span the world but are strongly represented in Australia and North
America with significant businesses in South America, Asia, Europe and southern
Africa.


Forward-Looking Statements


This announcement includes 'forward-looking statements' within the meaning of
Section 27A of the Securities Act of 1933, as amended, and Section 21E of the
Securities Exchange Act of 1934, as amended. All statements other than
statements of historical facts included in this announcement, including, without
limitation, those regarding Rio Tinto's financial position, business strategy,
plans and objectives of management for future operations (including development
plans and objectives relating to Rio Tinto's products, production forecasts and
reserve and resource positions), are forward-looking statements. Such
forward-looking statements involve known and unknown risks, uncertainties and
other factors which may cause the actual results, performance or achievements of
Rio Tinto, or industry results, to be materially different from any future
results, performance or achievements expressed or implied by such
forward-looking statements.


Such forward-looking statements are based on numerous assumptions regarding Rio
Tinto's present and future business strategies and the environment in which Rio
Tinto will operate in the future. Among the important factors that could cause
Rio Tinto's actual results, performance or achievements to differ materially
from those in the forward-looking statements include, among others, levels of
demand and market prices, the ability to produce and transport products
profitably, the impact of foreign currency exchange rates on market prices and
operating costs, operational problems, political uncertainty and economic
conditions in relevant areas of the world, the actions of competitors,
activities by governmental authorities such as changes in taxation or regulation
and such other risk factors identified in Rio Tinto's most recent Annual Report
on Form 20-F filed with the United States Securities and Exchange Commission
(the 'SEC') or Form 6-Ks furnished to the SEC. Forward-looking statements
should, therefore, be construed in light of such risk factors and undue reliance
should not be placed on forward-looking statements. These forward-looking
statements speak only as of the date of this announcement. Rio Tinto expressly
disclaims any obligation or undertaking (except as required by applicable law,
the City Code on Takeovers and Mergers (the 'Takeover Code'), the UK Listing
Rules, the Disclosure and Transparency Rules of the Financial Services Authority
and the Listing Rules of the Australian Securities Exchange) to release publicly
any updates or revisions to any forward-looking statement contained herein to
reflect any change in Rio Tinto's expectations with regard thereto or any change
in events, conditions or circumstances on which any such statement is based.


Nothing in this announcement should be interpreted to mean that future earnings
per share of Rio Tinto plc or Rio Tinto Limited will necessarily match or exceed
its historical published earnings per share.


Subject to the requirements of the Takeover Code, none of Rio Tinto, any of its
officers or any person named in this announcement with their consent or any
person involved in the preparation of this announcement makes any representation
or warranty (either express or implied) or gives any assurance that the implied
values, anticipated results, performance or achievements expressed or implied in
forward-looking statements contained in this announcement will be achieved.


For further information, please contact:


Media Relations, London                             Media Relations, Australia
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Media Relations, Americas
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Investor Relations, London                          Investor Relations, Australia
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David Ovington                                      Simon Ellinor
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Email: [e-mail]


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