Differential Cut-Off Grades

摘要

Detailed underground mine design and optimisation studies undertakenrnby the author over the past few years have clearly demonstrated thatrnadditional value can be created by varying the cut-off grade (COG)rnspatially throughout a deposit as well as over time.This additional valuerncan be particularly significant for marginal operations.rnThis paper,by way of worked examples,illustrates the conceptual andrnpractical considerations of applying a differential cut-off policy for anrnunderground mine to both maximise value and manage risks associatedrnwith production and metal price volatility.Consideration is given to bothrnthe design stage of a new mine and to the strategic and practicalrnapplication of a differential cut-off policy in an operating mine.