Abstract: The selection of mineral drillcore is of critical importance for the success of the archival facilities. In the broadest sense,only drillcore perceived as valuable to the national construction will be archived. This article describes the method used for the selection of mineral drillcore for the Western Australian core libraries. The criteria have been established whereby weighted selection parameters are used to determine a priority score. Using this priority score,drillcore can be ranked in order of importance with the most significant core selected for archiving.