626 MINING GEOLOGY/Mineral Reserves Table Major elements of mineral resource classification, excluding reserve base and inferred reserve base Identified resources Undiscovered resources Demonstrated Probability range Cumulative production Measured Indicated Inferred Hypothetical Economic Marginally economic Subeconomic Reserves Marginal Reserves Reserves Marginal Reserves Demonstrated subeconomic resources Includes non conventional and low grade materials Demonstrated subeconomic resources Includes non conventional and low grade materials Inferred reserves Inferred marginal reserves Inferred subeconomic resources Includes non conventional and low grade materials Includes non conventional and low grade materials Other occurrences Speculative Table Reserve base and inferred reserve base classification categories Cumulative production Economic Marginally economic Subeconomic Other occurrences Identified resources Undiscovered resources Demonstrated Probability range Measured Indicated Inferred Reserve base Reserve base Reserve base Reserve base Inferred reserve base Inferred reserve base Reserve base Includes non conventional and low grade materials Reserve base Includes non conventional and low grade materials Inferred reserve base Includes non conventional and low grade materials Table Russian classification of reserves Grade of geological certainty Reserves Explored Estimated A B C1 C2 Group of economic importance Economic Economic Economic Economic Subeconomic Subeconomic Subeconomic Subeconomic Resources Prognostic P1 P2 P3 subdivided into economic and sub economic In the Russian mining industry a classification of the explored reserves according to their mineable nature is used as follows: developed, prepared for extraction, and ready to extraction Resources are divided into three groups of prognostic resources (P 1, P 2, P 3) depending on the grade of geological certainty Main patterns of the Russian reserves/resources classification are shown on Table The Russian reserves Hypothetical Speculative Includes non conventional and low grade materials classification is used mostly in the states of the former USSR and also in some Eastern European countries The general procedure of a mineral reserve calculation is the same regardless of the concept that is used in making the ultimate classification, since it follows that no classification of any mineral reserve can be visualized completely until all necessary working data have been evaluated Two main groups of traditional resource estimations can be distinguished: The scalar-geometric methods or methods of geometrization The spatial (‘geostatistical’) methods In the first case a complex natural shape of mineral bodies are geometrized into defined geometric bodies, the volume of which can be calculated The following methods are distinguished: Methods of blocks Methods of geological sections Methods of isolines Methods of blocks can be divided depending on a geometrical arrangement of the exploration points