Ore Grade Reconciliation Techniques – A Review

Amoako Richard^1, and Al-Hassan Sulemana¹

¹Mining Engineering Department, University of Mines and Technology, Tarkwa, Ghana

Cite this paper

Amoako Richard and Al-Hassan Sulemana. Ore Grade Reconciliation Techniques – A Review. Journal of Geosciences and Geomatics. 2015; 3(5):116-121. doi: 10.12691/JGG-3-5-1

Abstract

The essence of ore grade reconciliation is to identify, analyse and manage variance between planned and actual results in a way that highlights opportunities. A consistent record of poor reconciliation is an indication that this variance has not been adequately managed. This would inevitably result in significant economic impact on mining companies. Unfortunately, the issue of poor reconciliation has been an age-old one most mining companies have been battling with and resulting in failure of several mining companies to estimate ore grade accurately, despite good grade control sampling and geological control. This paper reviews various practical and theoretical approaches to ore grade reconciliation, and further reveals inefficiencies in the mining value chain that contribute to poor reconciliation. Key recommendations, pertinent to observations and findings of the study, are thus made towards improving ore grade reconciliation.

Keywords

ore grade reconciliation, grade control, exploration, mine call factors, ore loss, dilution, sampling

Copyright

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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