International Guidelines for Defining Mineral Resources
The U.S. guidelines for defining mineral materials, such as uranium, differ from other international guidelines and standards. The U.S. Securities and Exchange Commission (SEC) regulates the disclosure of exploration results and the definition of mineralized materials and reserves under its Industry Guide 7 criteria.a The Canadian Securities Administrators have a different mineral resource classification system—the National Instrument 43-101 (NI 43-101).b Australasia adheres to the JORC (Joint Ore Reserves Committee) Code, and compliance is mandatory for companies listed on the Australian Stock Exchange. The Canadian NI 43-101 and JORC Code are similar, as they generally follow international guidelines set by the Committee for Mineral Reserves International Reporting Standards (CRIRSCO),c whereas the SEC guidelines differ from the NI 43-101 and JORC guidelines in some key areas.
In the late 1990s, CRIRSCO developed an International Framework Classification for Mineral Reserves and Mineral Resources. This committee included representatives from Australasia, Canada, Chile, Europe, and the United States. CRIRSCO defined mineral resources and reserves and their respective subcategories, Measured, Indicated, and Inferred Resources, and Proved and Probable Reserves (Figure 3.17). Following the CRIRSCO Agreement, the U.S. Society for Mining, Metallurgy, and Exploration (SME) released guidelines in 1999 (as did equivalent Canadian and Australasian organizations). However, The United States was the one CRIRSCO country whose regulator—the SEC—did not recognize the SME reporting standard and thus the CRIRSCO agreement guidelines.
Instead, the SEC published its own guidelines, delineated in its Industry Guide 7, “Description of Property by Issuers Engaged or to Be Engaged in Significant Mining Operations.” The main differences between the SEC and CRIRSCO guidelines are that the SEC has (1) a requirement of a standardized price based on the prevailing 3 years; (2) a restriction on the disclosure of proved and probable mineral reserves while other mineralized material is permitted (note that “mineralized material” is not clearly defined in the SEC guidelines); (3) a definition of a reserve as a “part of a mineral deposit which could be economically and legally extracted or produced at the time of the reserve determination” d; and (4) no clear
where the primary production is copper from a hydrothermal orebody, with subsidiary production of uranium, gold, and silver. The dominating effect of the Olympic Dam and other Australian uranium resources are also reflected in RAR comparisons (Figure 3.19).
Annual, worldwide requirements for fuel for existing power reactors amounts to about 67,000 tU. The world’s presently known Identified Resources of uranium, exploitable at or below $80 per kilogram of uranium, are some 3.75 million tonnes (Table 3.3) (NEA/IAEA, 2010). Existing known identified resources, based on present-day reactor technologies and if the resources are developed, are