
EP 177 | Rethinking Grade Control: When Ordinary Kriging Isn't Enough Video
Fresh Thinking by Snowden OptiroShow Notes
When does ordinary kriging stop being the best approach for grade control? In this episode of Fresh Thinking, Ian Glacken, Executive Consultant, and Dr Gregory Zhang, Senior Consultant at @SnowdenOptiro , explore direct SMU estimation and the circumstances where conventional ordinary kriging may not provide the best result. They discuss the challenges presented by highly skewed grade distributions, mixed populations and complex anisotropy, and consider alternative approaches including categorical indicator kriging (CIK), multiple indicator kriging (MIK) and localised MIK. Drawing on a case study, Ian and Gregory examine why different estimation methods should be tested and assessed against reconciliation results, rather than assuming a single approach will work for every deposit. They also emphasise an important point: more sophisticated estimation techniques are not a substitute for appropriate drilling and good-quality data. Listen to Fresh Thinking for technical insights and practical perspectives from Snowden Optiro's mining and geology experts.
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