Fresh Thinking by Snowden Optiro

In Part 2 of our Fresh Thinking by @SnowdenOptiro  two-part series, host Melanie Bully is joined by Senzeni Matondi to continue the discussion on why the most expensive mistake in grade control isn't necessarily mining low-grade material — it's making the wrong decision about whether material is ore or waste.
Following on from Part 1, this episode explores how mining operations can make better grade control decisions by understanding and managing uncertainty.
Melanie and Senzeni discuss why average grade alone doesn't tell the full story, how conditional bias and grade smoothing can affect ore and waste classification, and why local accuracy around the cut-off grade is so important.
They also explore grade control as a complete value chain — from sampling, QA/QC and geological logging through to estimation, dig planning, mining execution, stockpile management and mine-to-mill reconciliation. The conversation then turns to modern approaches to uncertainty and risk, including conditional simulation, probability-based ore classification and risk-based digline optimisation.
In this episode Melanie and Senzeni discuss:
Why two models with similar average grades can deliver very different operational outcomes
Conditional bias and the impact of grade smoothing
The importance of local accuracy around the cut-off grade
How ore loss and dilution result from misclassification • Why reconciliation reflects the performance of the entire grade control system
Moving from deterministic estimates to risk-informed decision-making
What best-practice grade control looks like at high-performing operations
The key message from this two-part series is simple: grade control isn't about producing the perfect block model — it's about consistently making better mining decisions.

What if the most expensive mistake in grade control isn't mining low-grade material — but making the wrong decision about what is ore and what is waste?
In this two-part episode of Fresh Thinking by Snowden Optiro, Senzeni Matondi, Principal Consultant, joins Melanie Bully, Senior Consultant, to explore why grade control is fundamentally a decision-making discipline, not simply a grade estimation exercise. 
In Part 1, Senzeni and Melanie unpack the operational and financial consequences of misclassification, including:
Ore loss — when valuable material is classified as waste and potentially lost forever
Dilution — when waste enters the ore stream, reducing head grade and consuming valuable processing capacity
Misclassification — and why it can result from accumulated uncertainty across sampling, geological interpretation, estimation, blast movement, survey accuracy and mining execution
Reconciliation — and why poor reconciliation can reflect issues across the entire mining value chain, rather than the resource model alone
The key takeaway? A technically sound grade estimate is only useful if it supports the right operational decisions.

If your resource model is statistically robust, why doesn't it always reconcile with production?
In this episode of Fresh Thinking by Snowden Optiro, Melanie Bulley and Senzeni Mandava Matondi explore why good resource estimates can still lead to disappointing reconciliation results.
They discuss the impact of grade smoothing, explain the concept of conditional bias, and explore why reproducing the average grade is only part of the story. The conversation also covers practical techniques used by resource geologists to assess estimation performance and improve local predictions that support better mining decisions.
Whether you're working in resource estimation, grade control or mine reconciliation, this episode offers practical insights into bridging the gap between statistical accuracy and operational performance.

How do you model mineralisation when geological boundaries aren't clearly defined?
In this episode of Fresh Thinking by  @SnowdenOptiro  , Senior Consultant, Melanie Bulley is joined by Principal Consultant, Senzeni Matondi to explore how Categorical Indicator Kriging (CIK) can be used to model diffuse mineralisation more objectively and consistently.
The discussion covers:
Why traditional wireframing can be challenging in diffuse deposits
How probability-based domaining improves consistency
The role of CIK in reducing subjectivity
Building more robust and defensible resource models
Whether you're a resource geologist, geostatistician or mining professional, this episode provides practical insights into one of the industry's most powerful domaining techniques.
Subscribe for more conversations on resource estimation, geostatistics and mining best practice from the experts at Snowden Optiro.

What do consultants see that mine sites often miss?
In this episode of Fresh Thinking bySnowden Optiro, Rayleen Hargreaves is joined by Ian Glacken to discuss the most common mine-to-mill reconciliation challenges, from stockpile management and siloed teams to understanding variance and improving decision-making.
Learn why reconciliation is more than a monthly report—it's a powerful tool for improving mine performance.