To: Little BM who wrote (21443 ) 2/20/2000 3:52:00 PM From: Claude Cormier Read Replies (2) | Respond to of 34075
LBM, Basically, according to the various sources I gatehered the information from, the definitions are:Proven (Measured) Reserves. Reserves for which (a) quantity is computed from dimensions revealed in outcrops, trenches, workings, or drill holes; grade and/or quality are computed from results of detailled sampling and (b) sites for inspection, sampling and measurement are so closely spaced and the geologic character is so well defined that size, shape, depth, and mineral content of the reserves are well established. In general, 25-50 meters in all directions of the 3-dimensional block that containing the proven reserves, is the spacing required between the samples. Probable (Indicated) Reserves. Reserves for which the quantity and grade and/or quality are computed from information similar to that for proven reserves, but the sites for inspection, sampling and measurements are farther apart or otherwise less adequately spaced. The degree of assurance, although lower than for proven reserves, is high enough to assume continuity between points of observation. In this case, 50-100 meters in all directions of the 3-dimensional block containing the probable reserves, is the spacing required between the samples. The difference between proven and measured (or probable and indicated) has to do with the feasibility work beeing done or not. IOW, the proven/probable are known to be mineable from a legal and economic point of view, not so with the measured/indicated. As for the possible/inferred category, it is everything else where not enough samples have been taken to bring the resource into the above categories.