ABSTRACT

The proportions of minerals in the heavy mineral suites of two volumetrically equal splits of the same sand sample were compared by use of the following quantitative methods of measurement: (1) number percentage (of sized suites); (2) weighted number percentage (based on frequency and weight of heavy minerals other than magnetite in each size grade); (3) weight percentage (based on frequency and weight of heavy minerals other than magnetite in a size grade, and on a selected specific gravity of a mineral); (4) hydraulic ratios; and (5) mineral ratios.

The results obtained by use of the (2) weighted number percentage and (3) weight percentage methods for the two splits show the lowest percentage of relative deviation. However, the (1) number percentage methods is preferred because it requires much less time and labor, although a little larger percentage of relative deviation resulted from its use. The (4) hydraulic ratios method is discounted because the relative deviation of the results obtained is not the lowest and because the method requires more time and labor than any other. If the (5) mineral ratios method is used, calculations should be on the basis of number percentage of a fine size grade of minerals having similar densities.