Rio Tinto s Ore Reserves and Mineral Resources are set out in full in its 2016 Annual report.

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1 Ntice t ASX Increase t Jadar Prject Mineral Resurces 2 March 2017 Included in Ri Tint s annual Mineral Resurces and Ore Reserves tables, released t the market tday as part f its 2016 Annual reprt, are increases in Mineral Resurces fr Ri Tint s 100 per cent-wned Jadar Lithium and Brates Mineral Prject in Jadar, Serbia. The updated Mineral Resurces are reprted in accrdance with the Australasian Cde fr Reprting f Explratin Results, Mineral Resurces and Ore Reserves, 2012 (JORC Cde) and the ASX Listing Rules. As such, the reprted increases relating t the Jadar prject requires the additinal supprting infrmatin set ut in this release and its appendix. Ri Tint s Ore Reserves and Mineral Resurces are set ut in full in its 2016 Annual reprt. During 2016, Jadar Mineral Resurces have increased by 19Mt frm 117Mt t 136Mt, a 16 per cent increase, including the first release f Indicated categry Mineral Resurces. The updated Mineral Resurce estimate cmprises: Indicated Resurce: % Li2O, 19.2% B2O3 Inferred Resurce: % Li2O, 13.0% B2O3 Ttal Mineral Resurce: % Li2O, 15.4% B2O3 Equivalent brate prduct resurces are 21Mt f B2O3. The upgrades have resulted frm cntinuing rebdy knwledge prgrammes undertaken at Jadar by Ri Tint. This increase in rebdy knwledge has been btained frm the fllwing wrk prgrammes which represent cmpnents f the Pre-Feasibility study currently underway: 3D seismic data prcessing and interpretatin. Cnslidating and analysing a large vlume f new gelgy data sets frm previus drilling campaigns. Reinterpreting and standardising all Jadar structural and gelgy mdels, allwed by the expanded range f available data sets. Imprved understanding f the lithstratigraphy and cntrls n mineralisatin. Adpting new Mineral Resurce estimatin methds. Page 1 f 7

2 Appendix Jadar Prject - Table 1 The fllwing table prvides a summary f imprtant assessment and reprting criteria used at the Jadar Prject fr the reprting f mineral resurces in accrdance with the Table 1 checklist in The Australasian Cde fr the Reprting f Explratin Results, Mineral Resurces and Ore Reserves (The JORC Cde, 2012 Editin). Criteria in each sectin apply t all preceding and succeeding sectins. Sectin 4 is mitted due n reprted Reserves.

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8 Year Rtary bit Diamnd bit # Hles Metres # Hles Metres , , , , , , , , , , , , , , ,402 Ttal 54 11, ,345

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17 2016 Annual reprt Mineral Resurces table, shwing line items relating t the Jadar changes Likely mining methd (a) Resurces at end 2016 Ttal resurces 2016 cmpared with 2015 Measured Indicated Inferred BORATE (b) Millins f tnnes B2O3 % Millins f tnnes B2O3 % Millins f tnnes B2O3 % Millins f tnnes B2O3 % Millins f tnnes B2O3 % Ri Tint interest % Jadar (Serbia) (c) U/G Likely mining methd (a) Resurces at end 2016 Ttal resurces 2016 cmpared with 2015 Measured Indicated Inferred LITHIUM Millins f tnnes Li2O % Millins f tnnes Li2O % Millins f tnnes Li2O % Millins f tnnes Li2O % Millins f tnnes Li2O % Ri Tint interest % Jadar (Serbia) (c) U/G Ntes (a) Likely mining methd: O/P = pen pit; O/C = pen cut; U/G = undergrund; D/O = dredging peratin. (b) Brates Resurces are reprted as in situ B2O3, rather than marketable prduct as in Reserves. (c) Resurces at Jadar increased fllwing additinal drilling and an updated gelgical mdel supprted by a 3D seismic survey. A JORC table 1 in supprt f these changes will be released t the market cntempraneusly with the release f this Annual reprt and can be viewed at ritint.cm/factsheets/jorc. Brate resurces are quted as prduct at 21mt B2O3. The equivalent in situ Resurce is 52 millin tnnes at 19.2 per cent B2O3 (Indicated) and 83 millin tnnes at 13.0 per cent B2O3 (Inferred). Page 2 f 7

18 Summary f infrmatin t supprt the Mineral Resurces estimates Increases in the Mineral Resurce estimate fr the Jadar Prject are supprted by the infrmatin set ut in the appendix t this release and lcated at ritint.cm/jorc in accrdance with the Table 1 checklist (Sectins 1 t 3) in the JORC Cde. All mdels (structural and gelgical) supprting the Mineral Resurce increase were updated t incrprate new and legacy drilling and 3D seismic data, leading t revised interpretatins f main structures, gelgy and Lwer Jaderite Zne grade cntinuity. The fllwing summary f infrmatin fr Mineral Resurce estimates is prvided in accrdance with rule 5.8 f the ASX Listing Rules. Gelgy and gelgical interpretatin The Jadar depsit, discvered in 2004 in western Serbia is a cncentratin f lithium and brates in a mineral at that time new t science, named Jadarite. It lies in a valley within flat-lying farmland area f 3.0 by 2.5 km, at depths frm 100 m t 720 m belw surface. The depsit includes three types f mineralizatin ccurring as stratifrm lenses f variable thickness, and hsted in gently dipping sequence f mainly fine-grained sediments that is crssed by faults: - Jadarite LiNaSiB3O7(OH) mineralizatin, s far unique t this depsit, is mainly cncentrated in three gently dipping tabular znes knwn as the Upper, Middle and Lwer Jadarite Znes (UJZ, MJZ and LJZ), - Sdium brates (mainly Ezcurrite, but als Kernite and Brax) as lenses interbedded with Jadarite, mainly enclsed r adjacent t the LJZ with a mre restricted areal distributin, - Gypsum, in the gypsum zne in the upper part f the stratigraphic sequence (sub ecnmic). All Jadar gelgy mdels cntain cmprehensive datasets and well defined interpretatins f the main structures and gelgical units. All mdels are supprted by varius drilling prgrams and a full range f dwnhle lgging and gephysical surveys, as well as 3D seismic survey f the extended depsit area, supprted by data prcessing and interpretatin, that has enhanced understanding f main structural fault systems cntrlling the lcatin f the Jadarite mineralisatin. Drilling techniques The HQ3 cre drilling was the predminant drilling type fr the Jadar depsit. Since 2004, a ttal f 310 drill hles (aggregate depth f 125,605 m) were drilled fr resurce definitin, getechnical, hydrgelgical, sterilisatin drilling purpses. This includes 11, large-diameter (500 mm), reverse circulatin drill hles and 14 PQ cre hles, that primarily, but nt exclusively, served fr the cllectin f a bulk samples required fr the metallurgical test-wrk prgram. Resurce estimatin is supprted by ttal f 175 drill hles with an aggregate depth f 100,622 m. The drill hles are nrmally planned and executed as vertical drill hles, except fr 37 inclined hles, that were rientated t intercept structural features. All hles were cnsistently dwnhle surveyed after drilling was cmpleted. Dwnhle lgging included varius prbes fr deviatin surveys, calliper and temperature as well as ther lgging methdlgies t detect and define the rientatin f bedding and structures and/r ther getechnical characteristics. Drill hle spacing (randm arrangement-semi grid) ranges frm 25 m in the central part, mving up t 500 m in the peripheral areas (130 m n average) and is cnsidered sufficient t establish gelgical and grade cntinuity t supprt the current Mineral Resurce classificatins. Page 3 f 7

19 Sampling, sub-sampling methd and sample analysis methd All samples fr assaying and density determinatin are taken frm predminant HQ3 (sme PQ3 and rarely NQ3) vertical r ccasinally inclined cre drilling. Sampling was cmpleted at RT drill cre strage facility, after lgging, based n sampling criteria determined by lithlgy and mineralgy, in accrdance with established frmal prtcls. Frm 2015 nwards, the sample lengths were assigned based n lithlgical gedmain bundaries, rather than at 1m fixed intervals, fllwing the maximum and minimum thickness criteria s established in the sampling prtcls. Since 2011, sample preparatin has been cmpleted at RT Jadar sample prep labratry lcated at the cre strage facility (rarely in an external ALS prep-labratry). After weighing, samples were immersed in water fr vlumetric measurement and then dried at temperature just belw 60ºC, fr minimum 24 hurs, and weighing again fr dry density calculatin. Samples were crushed t -1.4 mm in tw stages, subsampled in a rtary splitter t btain g, pulverized t -75 µm (>85 per cent passing) and then riffle split t prduce g pulp fr assaying. The unused rifle split pulp is stred in the sample archive. Sealed batches f pulverized samples were sent t the ALS Labratry fr assaying. Besides Li and B, a standard suit f assays includes: main xides as Fe2O3, CaO, MgO, Na2O, K2O, MnO and SrO. Additinal assays as, C, S, Cl and F were cnducted n selected samples fr prcessing tests purpse. Additinal assays f abut 26 ther elements have been cnducted n a limited number f batches, including pisnus and radiactive elements, t test fr by-prducts, deleterius cnstituents and t ensure that neither the mineralizatin nr its hst rcks are abnrmally hazardus. Blanks (every 40th) and Jadarite high and Lw grade standards (every 20th) were inserted in every batch, as well as sampling, crush and pulp duplicates (every 20th). Criteria used fr classificatin The Jadar resurce mdel fr the Lwer Jadarite Zne (LJZ) has been reprted as Indicated and Inferred Mineral Resurce categries. The resurce categry determinatin is based n a number f factrs: - Drill hle density in the LJZ - Slpe f Regressin gestatistical parameter - Gelgical cntinuity and cnfidence in the structural mdel - Grade cntinuity based n the semivarigram and sectinal interpretatins Indicated Mineral Resurce estimates are generally based n drill hle spacing less than 100m and Inferred Mineral Resurce n drill hle spacing greater than 100m and less than 200 m. Estimatin methdlgy The estimatin prcess was cmpleted using the Maptek Vulcan gelgical mdelling and Isatis gestatistical sftware packages. Mineralised dmains and backgrund mineralisatin were estimated in 3D space using rdinary kriging with up t fur estimatin passes t accunt fr the highly variable nature f the drilling density (25m t greater than 200m in plain view). A parent blck size f 25m (X) by 25m (Y) by 2m (Z) was used fr grade estimatin (n sub-celling). Data was cmpsited t 2m, the same vertical interval as the parent blck thickness in the vertical directin, t remve unwanted variability in the vertical directin. Statistical and varigraphy studies were undertaken and cnfirmed that the gestatistical apprach t grade estimatin was apprpriate. Page 4 f 7

20 Grade estimates were cnstrained laterally within a bundary plygn that cntains the majrity f drill hles frm the resurce database (grade estimates were nt extraplated utside f this plygn). Grade estimatin parameters were ptimized using Kriging Neighbrhd Analysis (KNA) studies, taking int accunt data density, kriging variance, and minimum and maximum numbers f samples. Reasnable prspects fr eventual ecnmic extractin Undergrund mining layuts utilize a variety f undergrund panel and stpe designs fr the Jadar Prject. A prerequisite fr undergrund mining is that surface subsidence is minimised. As such, stabilised stpe fill mining ptins are being develped. N minimum re thicknesses were assumed in the mdelling f the jadarite mineralisatin, given the zne ranges between 3 and 50m thick (average 15 m) and the need t cmplete stpe design trade-ff studies. The assessment f internal dilutin is dependent n the mining cut-ff grade and will be evaluated during the ecnmic assessment f the re material fr undergrund mining. A cut-ff grade f US$300/t fr Mineral Resurces has been applied t include nly material with prspects fr ecnmic extractin frm the available mineralised inventry. Sharp hanging wall and ftwall grade bundaries preclude the additin f significant thickness and therefre tnnes, unless the COG was significantly reduced. The pilt plant test-wrk n bulk samples frm LJZ has been successful in achieving the separatin f jadarite particles frm the fine-grained matrix, then disslutin in acid and refining t prduce marketquality lithium carbnate and bric acid prducts. While csts and recvery estimates are still under develpment within the current PFS study, it is clear that there is a viable prcessing rute t ecnmically prcess the jadarite and brate re frm recent pilt prcessing studies. Page 5 f 7

21 Cmpetent Persns Statement The material in this reprt that relates t Mineral Resurces is based n infrmatin prepared by Jrge Garcia, a Cmpetent Persn wh is a Member f the EFG and Mark Sweeney, a Cmpetent Persn wh is a Member f The Australasian Institute f Mining and Metallurgy, bth full-time emplyees f Ri Tint. Mr Garcia and Mr Sweeney have sufficient experience that is relevant t the style f mineralisatin and type f depsit under cnsideratin and t the activity being undertaken t qualify as Cmpetent Persns as defined in the 2012 Editin f the Australasian Cde fr Reprting f Explratin Results, Mineral Resurces and Ore Reserves. Each f Mr Garcia and Mr Sweeney cnsents t the inclusin in the reprt f the material based n the infrmatin that he has prepared in the frm and cntext in which it appears. Page 6 f 7

22 Cntacts ritint.cm n Twitter Media Relatins, United Kingdm Illtud Harri T M David Outhwaite T M Media Relatins, Australia Ben Mitchell T M Anthny Havers T M David Luff T M Investr Relatins, United Kingdm Jhn Smelt T M David Ovingtn T M Investr Relatins, Australia Natalie Wrley T M Rachel Strrs T M Nick Parkinsn T M Ri Tint plc 6 St James s Square Lndn SW1Y 4AD United Kingdm T Registered in England N Ri Tint Limited 120 Cllins Street Melburne 3000 Australia T Registered in Australia ABN Page 7 f 7