A scientific approach to analysing grade control has been applied at a number of mining operations. By dividing the grade control process into the various stages of data collection and interpretation, errors can be identified using reconciliations of production against predictions. The merits of different mining styles in large and small open pit mines are examined.
One factor in successful grade control is estimation of the expected ore loss and dilution. Empirical methods developed in two dimensions have been refined to enable 3D modelling of the effects on mineable grade and tonnage of varying the bench height, sampling orientation, and sampling Resolution.