GUIDELINE TO ASSESSING JORC COMPLIANCE REPORT (ORE RESERVE AND MINERAL RESOURCES) - ESTIMATION AND REPORTING OF ORE RESERVE

(Adapted from The JORC Code 2012 Edition, Australasian Code of Reporting Exploration Results, Mineral Resources and Ore Reserve; download JORC Code Template)



The Joint Ore Reserve Committee (JORC) in their description of reporting exploration results recommend these generic assessment criteria that investors can use to determine the integrity of a JORC Compliance report.

There are four key areas highlighted in the assessment criteria that investors should observe. These are:
  1. Sampling Technique and data
  2. Reporting of Exploration Data
  3. Estimation and reporting of Mineral Resources
  4. Estimation and reporting of Ore Reserve

4. Estimation and reporting of Ore Reserve


  • Mineral Resource estimate for conversion to Ore Reserves
Details of the basis in which mineral resources were converted to ore reserve must be noted first and foremost.

  • Site visits
Similarly note comment on any site visits undertaken by the Competent Person and the outcome of those visits.

  • Study status
It is vital to note the studies undertaken and to what level that enabled the conversion of mineral resources to ore reserve. Any code that requires further studies must be indicated together what has been extensively studied to the pre-feasibility stage. These should be accompanied by mine plan that technical and economically viable.

  • Cut-off parameters
The basis of the cut-off grade(s) or quality parameters applied enabling the conversion must be noted.

  • Mining factors or assumptions
This is a key area in the assessment. The reports must be able to note the assumptions used either by application of appropriate factors of through the optimisation and preliminary mine design. Those assumptions should be justified as to why, how and to what degree.
Mining factor, dillution, optimum pit geometry, equipment selection, general infrastructural requirements and recovery factors should be all noted together with a sensitivity analysis possible scenarios.
Note also the geotechnical parameters used to define the optimum pit limits including the pit slopes, stope sizes and how it dictates the overall mine plan/design in turn its implication on the ore reserve. Any key assumptions made here must be noted.

  • Metallurgical factors or assumptions
Note also the key assumptions made on selecting the metallurgical processes including but not limited to the mill recovery, head grade, technology, mineralogy, process flow, plant layout and tailing, and recovery methods. In addition any pilot projects/test works undertaken to establish the aforementioned assumptions and it practicability, applicability and appropriateness. 

  • Environmental
The status of studies of potential environmental impacts of the mining and processing operation and and possible environmental management strategies.

  • Infrastructure
Noted established infrastructures within the permitted land tenure, and availability of development area, water, power, roads, transports etc and how these can be accessed with ease.

  • Costs
Note the imminent cost associating with above discussed aspects together with appropriate capital and operational cost estimates, how they were derived and any possible fees and payment due as a result of mine development and mining (eg. compensations, royalties, levy etc)

  • Revenue Factors
At to the end, it a business and its all about profit. The report should on a balanced manner note the revenue generation assumptions made and the basis as to why and how they were derived. This includes but not limited to the, head grade, recovery, commodity price, exchange rates, transportation mining and processing costs and net smelter return. The derivation of assumptions made of metal price(s), for the principal metals, minerals and by-products.

  • Market Assessment
It is vital to note the marketing aspect of the comodity including current supply and demand, possible future outlook of the market. 
  • Economic
Note the economic variables  used in the economic analysis necessary to produce the Net Present Value (NPV) and the source and confidence level of these economic inputs including estimated inflation, discount rate, etc. The economic analysis should always be accompanied by a sensitivity analysis accounting for both worse and best case scenario.

  • Social
Note any social obligations with key stakeholders of the project.

  • Other
Other noted should include possible impacts, risk assessment, safety management plans, legal and political environment, any existing agreements in place, unresolved issues. Such are necessary to avoid undue inconvenience (if) and create general awareness of the operational environment and inherent obligations. In addition, the competent person feels should indicate any issue that may unreasonably interfere with the progress of the operation. 

  • Classification and Audits or reviews
Importantly note the basis for the classification of the Ore Reserves into varying economic confidence categories and the basis of classification. Note any audits or reviews of Ore Reserve estimates.

  • Discussion of relative accuracy/ confidence
The relative accuracy and confidence level in the Ore Reserve estimate should be discussed by the competent person. the determination and procedures used and the ore reserve estimation methods used whether statistical (geostatistics), geometrical methods. Note compositing and sampling density used to derive the classification. If computer software were used, details of the software should be provided together with input parameters. 
In all the level of accuracy and the confidence in the classification should be stated by competent person and any modifying factors that may have a material impact on Ore Reserve viability should be acknowledged.

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GUIDELINE TO ASSESSING JORC COMPLIANCE REPORT (ORE RESERVE AND MINERAL RESOURCES) - ESTIMATION AND REPORTING OF ORE RESERVE GUIDELINE TO ASSESSING JORC COMPLIANCE REPORT (ORE RESERVE AND MINERAL RESOURCES) - ESTIMATION AND REPORTING OF ORE RESERVE Reviewed by CEDRICK KAU on January 19, 2018 Rating: 5

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