SECTION 1 SAMPLING TECHNIQUES AND DATA

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1 Table 1 The following table provides a summary of important assessment and reporting criteria used at for the reporting of Mineral Resources and Ore Reserves in accordance with the Table 1 checklist in The Australasian Code for the Reporting of Exploration Results, Mineral Resources and Ore Reserves (The JORC Code, 2012 Edition). Criteria in each section apply to all preceding and succeeding sections. SECTION 1 SAMPLING TECHNIQUES AND DATA Criteria Sampling techniques Commentary Samples for geologic logging and assay are collected on 2 m intervals using dual rotary, mud rotary, and reverse circulation drilling methods. All reverse circulation drilling utilises a rotating cone splitter beneath a cyclone return system. Diamond core drilling is performed to collect samples for geotechnical testing (HQ, 63.5 mm diameter) and metallurgical testing (PQ, 85 mm diameter). Drilling techniques Drill sample recovery Drilling is predominantly by reverse circulation with lesser rotary and diamond drill core. Refer to Section 2: Drill Hole Information for a detailed breakdown of drilling by type and year. No direct recovery measurements of reverse circulation samples are performed. Sample weights are recorded from laboratory splits and the recovery at the rig is visually estimated for loss per 2 m drilling interval. Diamond drill core recovery loss of 5 cm or greater is recorded by the driller. Overall recovery from diamond drill core is approximately 92% for. Logging Standardised Rio Tinto Iron Ore logging systems are utilised for all drilling. Geologic and material type logging is performed on 2 m intervals for all reverse circulation drilling and 1 m for all diamond core drilling. Prior to 2006, diamond core was logged at intervals between 0.2 m to 4.0 m within mineralisation. All drill holes since 1997 are logged using downhole geophysical tools for gamma trace, calliper, gamma density, resistivity, magnetic susceptibility, and magnetic deviation. Since 2010, all geotechnical drill holes are logged using an acoustic televiewer for structural data measurements. Sub-sampling techniques and sample preparation Sub-sampling (dual rotary): Samples collected at 2 m intervals using a cyclone and a chisel splitter. A grab sample was collected and split. The A split was sent for analysis while the B-split was retained until assay completed, then discarded. Sub-sampling (mud rotary): 2m sampling interval. Coarse and fine samples were collected separately and combined by hand at the rig. Sub-sampling (reverse circulation): All reverse circulation drilling utilises the Rotating Cone Splitter (RCS) sampling system as per industry standards. Sample preparation (pre-2007): For the 1991, 2004 and 2005 drilling, no sample preparation data is available. Sample preparation (post-2011): The sample is oven dried at 105 degrees Celsius for a minimum of 24 hours. The sample is then crushed to approximately 3 mm using a Jaw Crusher and split to produce a 500 g subsample. The sub-sample is pulverised to 95% of weight passing 150 μm. Assay methods (pre-2007): For the 1991, 2004 and 2005 generation drilling, assay data includes a mixture of direct measurement of Fe by X-Ray Fluorescence (XRF) and back-calculated Fe from major oxide XRF assuming Fe = 100% - (sum of all major oxides). Assay methods (post-2007): All assaying of samples used in Mineral Resource estimates have been performed by independent, National Association of Testing Authorities (NATA) certified laboratories. Fe, SiO2, Al2O3, P, Mn, MgO, TiO2, CaO and S are assayed using Industry standard Lithium metaborate fusion and XRF analysis. Loss on Ignition (LOI) is determined using industry standard Thermo-gravimetric analyser (TGA). 1

2 Quality of assay data and laboratory tests Verification of sampling and assaying Standardised Rio Tinto Iron Ore quality control procedures are in place for all drilling post Field standards and field duplicates are systematically used. Laboratory preparation duplicates and assay duplicates are also included in the quality assurance and quality control protocol. Statistical analyses indicate a high level of precision and accuracy. Analyses of the duplicate dataset do not detect any bias in the field duplicate data. In 2007 Geostats Proprietary Limited were commissioned to complete a retrospective quality control assessment of the sampling data used to generate the 2006 geological interpretation and resource model for the Trial Pit and Central areas. The quality control analyses concluded that the data set has acceptable levels of reliability. Comparison of reverse circulation and twinned diamond drill core assay data distributions show that the drilling methods have similar grade distributions verifying the suitability of reverse circulation samples in the Mineral Resource estimate. Location of data points Data spacing and distribution Pre-2004: No data is available to ensure the accuracy of drill hole collar locations : Drill hole collars were surveyed by internal surveyors using the Kinematic DGPS method in both horizontal and vertical directions. The accuracy is unknown but the collars conform to the current topography. Post-2011: All drill hole collar locations at the deposit are surveyed to Local grid by Rio Tinto Iron Ore evaluation surveyors using Differential Global Positioning System (DGPS) survey equipment. Drill hole collar reduced level (RL) data is compared to detailed topographic maps and show that the collar survey data is accurate. The topographic surface is based on 10 m grid sampling of the 2012 Light Detecting and Ranging (LiDAR) survey, including spot heights from DGPS drilling collars and is considered robust. Drill spacing varies at the deposit between 25 m 50 m up to 800 m 100 m. The deposit is divided into a number of areas: Downstream, Centre Pit, Trial Pit, Superclean, and East. Downstream area: drill spacing is 800 m 100 m in the western most 1 km of this area, 400 m 100 m in the central 5 km and 100 m 100 m in the eastern most part of the area. The Trial Pit area: predominantly 50 m 50 m spacing with some areas collared using a triangular pattern with spacing of approximately 25 m 50 m. Central and East Areas: 100 m 100 m in both a triangular and square grid patterns. Superclean area: drilled on a triangular collar pattern with approximately 25 m 50 m spacing. Orientation of data in relation to geological structure Drilling is predominantly vertical intersecting the gently undulating strata at right angles. Sample security Pre-2011: No information is available on sample security. Post-2011: Laboratory samples (A splits) are collected by field assistants, placed onto steel sample racks, and transported by Centurion trucks to Ultra Trace Laboratories in Perth, Western Australia for analyses. Retention samples (B splits) are collected and stored in drums for 2 years at the Evaluation camp located on-site. Assay pulps are retained indefinitely at Rio Tinto Iron Ore facilities located at either Pannawonica or Dampier. Audits or reviews No external audits have been performed. Internal Rio Tinto Iron Ore peer review processes and internal Rio Tinto technical reviews have been completed. These reviews concluded that the fundamental data collection techniques are appropriate. SECTION 2 REPORTING OF EXPLORATION RESULTS Criteria Mineral tenement and Commentary The deposits are held under Mining Lease (ML) 248SA Section 107 by the Robe River 2

3 land tenure status Iron Associates (RRIA). RRIA is a joint venture, 53% owned by Rio Tinto Limited; 33% owned by Mitsui & Company, Limited; 10.5% owned by Nippon Steel Corporation; 3.5% owned by Sumitomo Metal Industries, Limited. Exploration done by other parties Initial exploration by Broken Hill Proprietary Limited in the 1960 s. RRIA acquired the tenements in Rio Tinto Limited acquired RRIA through the acquisition of North Mining Limited in Geology The deposit type is a channel iron deposit with mineralisation present as Tertiary Robe Pisolite. Basement rocks primarily shales and dolomites of the Wittenoom Formation, Mount McRae Shale, and Mount Sylvia Formation. Drill hole Information Table showing achieved drill hole spacing at the deposits. Year Hole Number BC001 BC x x 400 Achieved Drill Hole Spacing (m) Easting Grid Coordinate Ranges Shown 1600 x x x x x x x x x BC206 BC BC342 BC BC433 BC BC529 BC Table showing various drilling methods used at the deposits. Data aggregation methods Year Diamond core (DDH) Dual rotary with DDH tail Dual rotary Mud rotary with DDH tail Mud rotary Reverse circulation with DDH tail Total Total The data had been composited to 2 m for Mineral Resource estimation. No maximum or minimum grade truncations were performed. 3

4 Relationship between mineralisation widths and intercept lengths Diagrams Downhole lengths are reported which are essentially true width due to predominantly vertical drilling and gently folded, horizontal strata. Location of the Deposits 4

5 Balanced reporting Other substantive exploration data Not applicable. Rio Tinto Iron Ore has not specifically released exploration results for these deposits. Surface mapping data has been collected across the area in 2005 at a scale of 1:5,000. Further work Pending outcomes from the current project study, infill reverse circulation drilling is planned for all deposits to a planned spacing of 50 m 50 m. SECTION 3 ESTIMATION AND REPORTING OF MINERAL RESOURCES Criteria Database integrity Commentary All drilling data is securely stored in an AcQuire geoscientific information management system managed by a dedicated team within Rio Tinto Iron Ore. The system is backed up nightly on servers located in Perth, Western Australia. The backup system has been tested in 2013, demonstrating that the system is effective. The drilling database used for Mineral Resource estimation has been internally validated by Rio Tinto Iron Ore personnel. Site visits The Competent Person visited in Geological interpretation Geological modelling is undertaken by Rio Tinto Iron Ore senior geologists. The method involves interpretation of downhole stratigraphy using surface geologic mapping, lithological logging data, downhole gamma data, and assay data. Cross-sectional interpretation of each stratigraphic unit is performed followed by interpretation of mineralisation and hydration boundaries. Three-dimensional wireframes of the sectional interpretations are created to produce the geological model. Dimensions The deposit is approximately 17 km in length, 2.8 km in width and extends to a depth of 200 m below the surface. Estimation Separate block models have been created for the and Downstream 5

6 and modelling techniques deposits. The block models have been divided into a number of areas with varying block dimensions. These are detailed the table below. Area Easting Northing Elevation Parent (m) Sub-block (m) Downstream Downstream Overall Centre Trial Pit 18,800 24,800 24,800 26,200 26,000 34,950 27,800 34,950 28,500 29,900 10,400 11, x 50 x x 6.25 x x 50 x x 6.25 x x 50 x x 6.25 x x 50 x x 6.25 x x 25 x x 6.25 x 1 The block model orientation is grossly aligned with the deposit trend, hence it trends west to east and has no dip or plunge. Mineralised domains are estimated by ordinary kriging and non-mineralised domains are estimated by inverse distance weighting to the first power. Blocks not estimated received the weighted average domain grade. The estimated model was validated using a combination of visual, statistical and Multivariate Global Change of Support techniques. There is no production data to reconcile model quality. Moisture All Mineral Resource tonnages are reported on a dry basis. Cut-off parameters Mining factors or assumptions Metallurgical factors or assumptions Environmental factors or assumptions The resource is defined by geological units. The Hard Pisolite (TPH), Friable Pisolite (TPF), Mixed Pisolite (TPX) units are included in the Mineral Resource. Development of this Mineral Resource estimate assumes mining using standard Rio Tinto Iron Ore equipment. The assumed mining method is conventional truck and shovel open pit mining with 4 m benches. Mining practices will include detailed grade control utilising blast hole data. It is assumed that the mineralisation can be dry processed following dewatering. Higher clay zones are expected to be beneficiated by wet process to remove clay. Rio Tinto Iron Ore has an extensive environmental and heritage approval process. A detailed review of these requirements is undertaken in the current Order of Magnitude study. No issues were identified that would impact on the Mineral Resource estimate. Bulk density For the deposit, dry bulk density is measured using accepted gamma-density data collected at 10 cm intervals from downhole geophysical sondes. Accepted gamma-density data is corrected for moisture using diamond drill core drilled throughout the deposit. Bulk density is estimated using ordinary kriging in mineralised zones and inverse distance weighted to the first power in non-mineralised zones. For the Downstream deposit, the average dry bulk density was scripted into the model. Classification The Mineral Resource includes the classifications: Measured, Indicated, and Inferred with additional material (greater than 50% Fe) set as unclassified. The Competent Person is satisfied that the stated Mineral Resource classification reflects the geological controls interpreted and the estimation constraints of the deposits. Audits or reviews Discussion of relative accuracy/ confidence All stages of Mineral Resource estimation have undergone an internal peer review process, which has documented all phases of the process. The Mineral Resource estimate has been accepted by the Competent Person. Rio Tinto Iron Ore operate multiple mines in the Pilbara region of Western Australia. The Mineral Resource data collection and estimation techniques used for are consistent with those applied at similar deposits which are being mined. Reconciliation of actual production with the Mineral Resource estimates for individual deposits is generally accurate to within ten percent for tonnes on an annual basis. This result is indicative of a robust process. Accuracy and confidence of Mineral Resource estimation is consistent with the current level of study (Order of Magnitude). 6