How much would a blending stockpile reduce variation?

A blending stockpile generally reduces the amount of grade variation between parcels of material of a moderate size, because the parcels of material on reclaiming are mixtures of the parcels of material which were stacked. This general principle will be illustrated using both mathematical and computer models for the geometry of a stockpile and using both actual grade data and a variogram to describe the input variation. Some applications to the planning of mining operations will be briefly discussed.