Improving mineral resource reconciliation using ordinary kriging with improved data – A case study

Abstract

Reconciliation of mineral resource model with grade control model of the Teberebe orebody had some important variations. These were very significant where there were inadequate drill hole data and geological interpretation. Grade control drilling produced more geological data and allowed for improved interpretation of the geology. There was therefore the need to remodel the mineral resource with the additional data obtained from grade control drilling. Ordinary kriging was used to re-evaluate the mineral resource. The study indicated that the new model reconciled practically better with the grade control model than the old one. It produced lower grade but higher tonnage than the old model using the same cut-off grade of 0.56 g/t. It also produced higher total gold recovered than the older one. The new resource model, unlike the old one, included the D zone of the orebody. It was recommended that grade control, sampling and modeling should include the D zone.