Podcast
Questions and Answers
What is the maximum reasonable time period for estimating eventual economic extraction for gold deposits?
What is the maximum reasonable time period for estimating eventual economic extraction for gold deposits?
Which category of Mineral Resource is characterized by the highest level of confidence in estimation?
Which category of Mineral Resource is characterized by the highest level of confidence in estimation?
What should be clearly stated and described in a Public Report regarding mineral resource estimates?
What should be clearly stated and described in a Public Report regarding mineral resource estimates?
Inferred Mineral Resources are characterized by what level of confidence compared to Indicated Mineral Resources?
Inferred Mineral Resources are characterized by what level of confidence compared to Indicated Mineral Resources?
Signup and view all the answers
What determines the appropriate category of Mineral Resource classification?
What determines the appropriate category of Mineral Resource classification?
Signup and view all the answers
What defines a Mineral Resource according to its economic extraction potential?
What defines a Mineral Resource according to its economic extraction potential?
Signup and view all the answers
Which category is NOT part of the classification hierarchy for Mineral Resources?
Which category is NOT part of the classification hierarchy for Mineral Resources?
Signup and view all the answers
What must be disclosed in public reports when economic extraction relies on untested practices?
What must be disclosed in public reports when economic extraction relies on untested practices?
Signup and view all the answers
What does the term 'reasonable prospects for eventual economic extraction' imply?
What does the term 'reasonable prospects for eventual economic extraction' imply?
Signup and view all the answers
Which statement correctly reflects the interpretation of the word 'eventual' in the context of Mineral Resources?
Which statement correctly reflects the interpretation of the word 'eventual' in the context of Mineral Resources?
Signup and view all the answers
What must be considered when making a decision between Indicated and Inferred Mineral Resources?
What must be considered when making a decision between Indicated and Inferred Mineral Resources?
Signup and view all the answers
How should the estimates of tonnage and grade for Inferred Mineral Resources be expressed?
How should the estimates of tonnage and grade for Inferred Mineral Resources be expressed?
Signup and view all the answers
What should be avoided when publicly reporting Mineral Resources?
What should be avoided when publicly reporting Mineral Resources?
Signup and view all the answers
In what scenario should the term 'Ore Reserves' be used?
In what scenario should the term 'Ore Reserves' be used?
Signup and view all the answers
What should be done when mineral resource estimates involve significant uncertainties?
What should be done when mineral resource estimates involve significant uncertainties?
Signup and view all the answers
Study Notes
Mineral Resource Reporting
- Mineral Resource: A concentration/occurrence of economically-interesting material in Earth's crust, with reasonable prospects for extraction. Location, quantity, grade, geological characteristics and continuity are known, estimated, or interpreted from geological evidence.
- Categories (in increasing confidence): Inferred, Indicated, Measured.
- Portions of a deposit with no economic extraction prospects are excluded.
- "Reasonable Prospects" requires a Competent Person's judgment on technical/economic factors influencing extraction.
- Includes mineralization like dumps and tailings, with estimation via exploration and sampling. May contain Ore Reserves.
- Estimates may include material below cut-off grade to ensure adequate body size/continuity for assessing mining approaches.
- Diluting material inclusion and commentary on its materiality are crucial.
- Assumptions regarding "eventual economic extraction" need clear disclosure. Timeline considerations vary by commodity (e.g., coal >50 years, gold ~10-15 years).
- Adjustments to data (e.g., grade cuts/factors) must be clearly documented.
- Some reports (e.g., coal inventory reports, exploration reports to government) may include all mineralization even if not economically viable.
Inferred Mineral Resource
- Lowest confidence category.
- Based on estimated geological evidence (like outcrops, trenches, drill holes).
- Tonnage, grade, and mineral content estimated with a low level of confidence.
- Assumes/infers geological and grade continuity, but not verified.
- Often upgrades to higher categories with further exploration.
Indicated Mineral Resource
- Moderate confidence category.
- Based on exploration, sampling, and testing information.
- Locations are sufficiently spaced to assume continuity but not enough to confirm.
- Higher confidence than Inferred, lower than Measured.
- Data allows confident interpretation of geological framework and assumes continuity of mineralization.
- Sufficient confidence for applying technical/economic parameters and evaluating economic viability.
Measured Mineral Resource
- Highest confidence category.
- Based on detailed, reliable exploration, sampling, and testing information with nearby locations confirming continuity.
- No reasonable doubt regarding estimated tonnage/grade and that variations don't significantly impact viability.
- High confidence in geology and controls of the deposit.
- Sufficient confidence for applying technical/economic parameters and evaluating economic viability.
Ore Reserve
- Economically mineable portion of Measured/Indicated Mineral Resource (includes diluting material & losses during mining).
- Assessments and studies consider mining, metallurgical, economic, marketing, legal, environmental, social, and governmental factors.
- Demonstrates extraction feasibility.
- Categories (in increasing confidence): Probable, Proved.
Probable Ore Reserve
- Lower confidence than Proved.
- Sufficient quality to support deposit development decisions.
- Based on Indicated Mineral Resources or, in some cases, Measured Mineral Resources.
Proved Ore Reserve
- Highest confidence category representing the most viable portion.
- Based on Measured Mineral Resources.
- Represents the highest degree of confidence.
- Conversion between categories depends on Modifying Factors uncertainty.
- Can't directly convert an Indicated Mineral Resource into Proved Ore Reserve.
Reporting Considerations
- Reporting must be in distinct categories (Inferred, Indicated, Measured for Mineral Resources; Proved, Probable for Ore Reserves). No combined figures.
- Tonnage and grade figures reflect estimate's accuracy (rounding, significant figures). Inferred Mineral Resource estimates may use qualifying terms (e.g., "approximately").
- Ore Reserves & Mineral Resources must be described separately; not aggregated.
- Specify if Mineral Resources are inclusive or additional to Ore Reserves.
- Discuss adjustments made to resource/reserve estimates (e.g., cutting/factoring grades).
- Detail uncertainties in estimation methodology.
- Table 7.1 provides criteria for reports, discuss relevant factors only if materially affecting estimates.
- Discuss any material uncertainties/unresolved matters impacting estimates.
- Reconciliation of revised statements is crucial.
- "Ore" and "Reserve" terminology used only when technical feasibility and economic viability are established.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the essential concepts of mineral resource reporting, including definitions, categories, and the criteria for assessing economic extraction prospects. This quiz covers the role of competent judgment in evaluation and touches on topics such as mineralization, estimation, and the significance of dilution in the reporting process.
