- GeoRef, Copyright 2008, American Geological Institute. Reference includes data from Bibliography and Index of North American Geology, U. S. Geological Survey, Reston, VA, United States
Efficiency of sieving is indicated by the percentage of finer near-mesh particles that fail to pass through any sieve. The percentage of finer particles retained is a function of the load on the sieve and the length of time of sieving. A graph shows maximum loads for 3-inch diameter sieves at one-fourth and one-half phi intervals. The maximum load is set at five particles per aperture. Sieving time is ten minutes.