Changes to Pilbara Mineral Resources

27 February 2019

Rio Tinto’s 2018 annual report, released to the market today, includes significant changes in estimates of Mineral Resources for Pilbara iron ore deposits in Western Australia, compared to the previous estimates in the 2017 annual report.

The updated Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves, 2012 (JORC Code) and the ASX Listing Rules. Supporting information relating to the changes is set out in this release and its appendices. Mineral Resources are quoted on a 100 per cent basis. Rio Tinto’s interests are listed on pages 5 and 8.

Rio Tinto’s Mineral Resources are set out in full in its 2018 annual report. Mineral Resources are reported as dry in-situ tonnages in addition to Ore Reserves.

In 2018, technical work was conducted across multiple deposits with over 700,000 m drilled. A portion of this has contributed to the significant changes in the following Mineral Resources and are detailed in this release and its appendices:

  Mineral Resources
Music Hall / Old Vic  First reporting of Mineral Resources for Music Hall and Old Vic has added to Hamersley Iron:
• 225 Mt of Marra Mamba ore
• 58 Mt of Detrital ore
Western Hill Update to the Mineral Resources for Western Hill has added to the Robe River JV:
• 112 Mt of Brockman ore
• 42 Mt of Brockman Process ore
• 12 Mt of Detrital ore