Mineral inventory estimation in vein type gold deposits: case study on the Eastmain deposit

CIM Bulletin, Vol. 82, No. 930, 1989

Clayton Deutsch, Computer Services, Placer Dome Inc.

Estimating the mineral inventory and the mineable reserves in underground gold deposits is a difficult problem. This paper will consider a number of estimation techniques and recommend a method based on the geostatistical technique of indicator kriging. A general discussion on the modelling of vein deposits is followed by a more detailed presentation of the geostatistical estimation method. For comparison, the mineral inventory for one vein of the Eastmain deposit in northern Quebec has been calculated using a number of methods. The results obtained from polygonal and sectional methods are compared to the recommended geostatistical procedure. It is shown that this geostatistical method works very well when constrained by the available geological information. The advantages are an unbiased grade estimate without cutting any data and an estimate that accounts for the specific grade and structural continuity found in the vein.
Mots Clés: Eastmain, Ore reserves, Mineral inventory, Vein type deposits, Geostatistics, Indicator kriging, Gold deposits