Grade control for Australian open pit gold mines / Контроль качества на открытых золотых рудниках Австралии

The deposits exploited in Australian open pit gold mines are often small and of low grade with highly variable gold distributions. Consequently, they require detailed grade control. The nature of these grade control programmes is outlined together with a description of the various computational methods used. Particular attention is given to geological input into the various stages of the grade control program so as to ensure the reliability of sampling; to aid the production of bench extraction outlines; and to predict and minimize dilution and ore loss. The application of geostatistical techniques in this respect is also critically examined.