An approach to regional geochemical mapping is outlined utilizing differences among mean metal concentrations for soil associated with individual parent materials. Initially the area of study is divided into parent material-based subareas for soil collection. Separate mean and variance metal values are estimated for each parent material and Duncan's Multiple Range Test is used to evaluate the statistical significance of among mean differences. Results are summarized in map form showing only compositionally distinctive parent materials or parent material groups and their associated mean and range values.This approach was tested in the Rosetown–Outlook area of south-central Saskatchewan. Results suggest that, in total, fewer than 10 samples are required per parent material to produce stable maps for copper, iron, manganese, and zinc in this 10 000 km2 area. Because of the limited number of samples needed, the method is both rapid and relatively inexpensive. It is therefore ideally suited for regional geochemical surveying, particularly in relatively arid areas where conventional lake and stream sediment-based procedures are not applicable.