EVALUATION AND APPLICATION OF REFERENCE MATERIALS FOR THE ANALYSIS OF ROCKS AND MINERALS

For a reference sample to be useful in the analysis of rocks, the concentrations in it of as many constituents as possible must be known as accurately as possible. Results of inter-laboratory collaborative analyses of such materials are generally widely disparate. Numerous procedures have been proposed for deriving "best values" for each constituent from such scattered data. All such schemes have, on occasion, produced questionable results. This work describes the schemes and combinations of them, as well as proposing a possible alternative. Suggestions are made for minimizing the effects of the resulting uncertainties in the compositions of reference samples, when they are used in the analysis of unknowns.