What are some of the best practices and standards for mineral resource and reserve estimation and reporting?

1 Mineral resource and reserve definitions

Mineral resources and reserves are not the same thing. Mineral resources are the portions of a mineral deposit that have reasonable prospects for economic extraction, based on geological, technical, and economic factors. Mineral reserves are the subsets of mineral resources that have demonstrated economic viability, based on detailed engineering, environmental, and social studies. Both mineral resources and reserves are classified into categories according to the level of confidence and the degree of modification of the original mineralization.

2 Estimation methods and techniques

Mineral resource and reserve estimation involves applying various methods and techniques to estimate the tonnage and grade of the mineral deposit, as well as the modifying factors that affect its economic extraction. Some of the common methods and techniques include geological mapping, sampling, drilling, assaying, geostatistics, block modeling, grade interpolation, cut-off grades, dilution, and recovery. The choice of method and technique depends on the type, shape, size, and distribution of the mineralization, as well as the available data, technology, and expertise.

3 Reporting codes and standards

Mineral resource and reserve estimation and reporting must follow internationally recognized codes and standards that ensure consistency, transparency, and credibility of the information. Some of the most widely used codes and standards include the JORC Code, the CIM Standards, the NI 43-101, the SAMREC Code, and the CRIRSCO Template. These codes and standards define the terminology, classification, criteria, and guidelines for mineral resource and reserve estimation and reporting, as well as the qualifications, responsibilities, and competencies of the professionals involved.

4 Best practices and principles

In addition to complying with the codes and standards, mineral resource and reserve estimation and reporting should also adhere to some best practices and principles that reflect the current state of knowledge and practice in the mining industry. These include applying the concept of materiality, meaning all information that could influence decision-making of investors or stakeholders should be disclosed and explained. Additionally, reasonableness should be applied, meaning all assumptions, methods, and results should be realistic, logical, and supported by evidence. Furthermore, transparency should be applied, meaning all information should be clear, accurate, complete, and verifiable. Finally, competence should be applied, meaning all professionals involved should have the relevant education, experience, and skills to perform their tasks.

5 Benefits and challenges

Mineral resource and reserve estimation and reporting have many benefits and challenges for the mining industry. Providing reliable and consistent information for planning, designing, financing, operating, and evaluating mining projects and operations is one benefit, as well as enhancing the confidence of investors, regulators, communities, and other stakeholders. It also promotes the best practices and standards of professionalism, ethics, and governance in the mining industry. However, dealing with the inherent uncertainty and variability of mineral deposits is a challenge, as well as keeping up with evolving codes and standards, technologies, and market conditions that affect estimation and reporting. Additionally, addressing environmental, social, and legal aspects that influence economic extraction of mineral resources and reserves must be taken into consideration.

6 Resources and references

If you want to learn more about mineral resource and reserve estimation and reporting, you can consult the website of the Committee for Mineral Reserves International Reporting Standards (CRIRSCO), which provides access to relevant codes and standards, definitions, guidelines, and publications. Additionally, the book Mineral Resource and Ore Reserve Estimation: The AusIMM Guide to Good Practice offers comprehensive coverage of principles, methods, and techniques of mineral resource and ore reserve estimation. Lastly, Edumine's course Mineral Resource Estimation provides an online learning program that covers fundamentals, methods, applications, practical exercises, and software tools.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?