Company: RTNTF
Filing Date: 2025-02-20
Form Type: 20-F
Source: 0001628280-25-006642
Chunk: 443

Company: RIO TINTO LTD
Filing Date: 2025-02-20
Form: 20-F
Chunk 443
---
 Mineral Resources, Mineral Reserves and reconciliation reporting. The Technical Assurance team also advises on disclosure obligations, monitors the external reporting environment and facilitates internal audits. Internal Auditing Mineral Resources and Mineral Reserves internal audits are conducted by independent external consulting personnel in a programme managed by Orebody Knowledge Technical Assurance. Material findings are reported outside of the product group reporting line to the ORSC, and all reports and action plans are reviewed by the ORSC for alignment to internal and external reporting standards. During 2024, three internal Mineral Resources and Mineral Reserves audits were completed. Geoscientific information management and assurance We employ industry-standard drilling, sampling, assaying and quality assurance/ quality control (QA/QC) practices supported by formally documented procedures. Diamond core and reverse circulation are our primary drilling methods. We use other methods such as sonic and air core if appropriate for the style of deposit. Drill hole locations are typically confirmed by high- precision differential Global Positioning System (GPS) and down-hole trace positioning is primarily achieved by gyroscopic survey. Drill sample recovery is typically recorded, and all geological data is collected by qualified geoscientific professionals. Geological logging consistency is secured via formal logging procedures and training, reference materials, application of geological code libraries and digital logging directly to the geological database. On-site or commercial laboratories provide appropriate analytical (assaying) techniques, according to the commodity and style of deposit. Reliability of assay data is maintained via QA/QC procedures, which monitor assay accuracy and precision through the analysis of blanks, sample duplicates and matrix-matched certified reference materials. Our geoscientific information management standard is the industry-leading acQuire system and we employ strict QA/QC criteria to ensure only high-quality assay data is uploaded to a project’s database. Mineral Resources and Mineral Reserves risk management Risks to our Mineral Resources and Mineral Reserves estimates are managed through comprehensive risk assessments undertaken in support of the annual reporting cycle. Risks are identified and managed by verifying controls, determining and undertaking suitable actions to remove or reduce the risk, conducting reviews, and maintaining compliance with standards and procedures. Risks are managed through a commercial risk management solution. At the end of each reporting cycle, we analyse the Mineral Resources and Mineral Reserves risks across all business units to ensure both consistency of reporting and determine any Group-wide risks to the various processes.

| Annual Report on Form 20-F 2024 | 301 | riotinto.com |

Production, Mineral Reserves, Mineral Resources and operations

Qualified Persons

|                            | Association(a)