Ore deposit models form the basis for numerous other economic decisions
in the mining process. The success of these economic decisions therefore
depend directly on the accuracy of the ore evaluation process. The Geology Department at the Sishen Iron Ore Mine is responsible
for the generation of a reliable geological computer model of the rock
material with predicted grades. This information is then utilised for
further ore reserve calculations, mine planning, production scheduling
and grade control. Owing to a very complex geological orebody, grades and beneficiation
characteristics differ significantly from sample to sample. This means
that ore evaluation is a difficult process and great reliance is placed on
computer techniques. In 1993, preparation for the ISO 9002 quality certification of the mine
motivated the Geology Department to hold formal `problem solving'
sessions in order to identify and revise problem areas in operating