Dutta, S, Lal, A, Chittora, V, Chordia, L & Tailor, D 2015, 'Ore dilution control practised at Sindesar Khurd Mine of Hindustan Zinc Ltd', in Y Potvin (ed.), Design Methods 2015: Proceedings of the International Seminar on Design Methods in Underground Mining, Australian Centre for Geomechanics, Perth, pp. 553-568, https://doi.org/10.36487/ACG_rep/1511_35_Dutta (https://papers.acg.uwa.edu.au/p/1511_35_Dutta/) Abstract: Ore dilution has been a major operating challenge in the underground open stoping operations at Sindesar Khurd Mine of Hindustan Zinc Ltd, India. The impact of ore dilution, affecting both the direct and indirect cost of production, has been detrimental to the economics of the mine showing chances of exponential effect in hampering profitability. The authors provide an overview of the various issues influencing dilution in the underground operations. This paper highlights the stages of stringent orebody delineation, grade modelling/contouring, proper stope development, scientific stope design and sequencing, controlled drilling and blasting, and improving mine management. It reviews the entire system improvement that has steadily resulted in effective reduction in planned dilution (17.23-5.72%) and external dilution (8.833.28%) from 20112012 through to 2014-2015.