EP 156 | Part 3 of 7: Conditional Simulation

In this episode of Fresh Thinking by Snowden Optiro, Ian Glacken and Susan Havlin explore localised conditional simulation (LCS) and its role in modern resource estimation workflows. Building on earlier discussions around estimation methods, recoverable resources, and conditional simulation, this episode brings everything together to explain how LCS converts multiple simulation realisations into a single, practical block model—while preserving realistic grade variability.  Key topics include:  What localized conditional simulation is and why it matters How localization transforms multiple realizations into a single model The role of the E-type estimate in ranking and distribution Differences between LCS and traditional ordinary kriging How LCS supports recoverable resource estimation at the SMU scale The origins of localization and its relationship to methods like uniform conditioning and MIK

In this episode of Fresh Thinking by ‪@SnowdenOptiro‬, Susan Havlin and Ian Glacken explore the fundamentals of conditional simulation and its role in modelling grade variability and uncertainty in mineral resource estimation. They discuss how simulation differs from traditional methods like kriging and uniform conditioning, why capturing uncertainty is critical for modern mining decisions, and how multiple realizations can provide valuable insight into upside and downside risk.  The conversation also touches on practical challenges, including reporting to the market and integrating uncertainty into mine planning workflows.

In this episode of Fresh Thinking by @SnowdenOptiro , we explore recoverable resource methods and how they help bridge the gap between resource models and what is actually mined. We discuss key approaches used across the industry, including Uniform Conditioning (UC) and Multiple Indicator Kriging (MIK), outlining how they address grade smoothing and improve predictions at the mining scale. We also cover the strengths and limitations of these methods, particularly their reliance on variograms and their inability to capture uncertainty. This episode sets the stage for the next discussion on conditional simulation, where uncertainty and variability can be modeled more effectively. Topics covered: What are recoverable resources? Why traditional estimation methods fall short Uniform Conditioning (UC) explained Multiple Indicator Kriging (MIK) explained Strengths and limitations of recoverable resource methods Subscribe for more insights on geostatistics, resource estimation, and mining best practices. Subscribe to Fresh Thinking by Snowden Optiro for more insights on geostatistics, resource estimation, and mining best practices.

Episode 154 of Fresh Thinking by Snowden Optiro kicks off a 7-part series on modern resource estimation. In this episode, we cover the fundamentals of ordinary kriging, its strengths and limitations, and introduce key concepts like grade smoothing, SMU, and recoverable resources. Featuring Ian Glacken and Susan Havlin.

Discover the fascinating origins of Australia's nickel industry in this episode of Fresh Thinking by ‪@SnowdenOptiro‬. Principal Consultant, Jan Graham, sits down with Executive Consultant, Ian Glacken, to explore the pivotal moment that sparked it all—the discovery of nickel at Kambalda in 1966. From early prospecting and geological insight to rapid development and industry-wide impact, this story highlights the role of luck, lateral thinking, and persistence in shaping one of Australia's most significant mining sectors. Learn how a single drill hole, KD1, transformed Western Mining Corporation and led to decades of nickel production across Australia.  If you enjoy mining history, geology, and industry insights, don't forget to like, subscribe, and follow Fresh Thinking by ‪@SnowdenOptiro‬ .

What does it really mean to sign off on a mineral reserve? In this episode of Fresh Thinking, Tarrant Elkington (General Manager, Snowden Optiro) is joined by Allan Earl (Executive Consultant Mining) to discuss the real responsibility behind reserve sign-off and what it takes to stand behind it with confidence.  From understanding the full value chain to applying critical review across technical inputs, this conversation explores where things can go wrong, and how to avoid it. If you're working towards becoming a Competent Person, or already signing off on reserves, this is well worth a listen. Key moments: 01:14 – What "signing off" actually means 02:23 – Who should be the Competent Person 03:47 – What you're truly responsible for 05:30 – What a "critical review" really involves 08:45 – Where people get it wrong 11:07 – Should you be signing off? 15:36 – Final takeaway: ownership and accountability If you would like to contact Tarrant and Allan: contact(at)snowdenoptiro.com 🎧 Fresh Thinking by Snowden Optiro is rapidly becoming the best mining podcast globally, and is available as an audio podcast on all major podcast platforms, and in video format on Snowden Optiro's YouTube channel. Snowden Optiro: Snowden Optiro is a resources consulting and advisory group that provides independent advice, consulting and training to mining and exploration companies, their advisors and investors. We help mine developers to advance their projects, mining companies to improve their operations and their professionals, and investors to de-risk their investments by the provision of quality advice, training and software in the field of Mineral Resources and Mineral/Ore Reserves. Explore more: https://snowdenoptiro.com/

In this episode of Fresh Thinking by Snowden Optiro, Jamie Oppelaar (Senior Consultant) and Tarrant Elkington (General Manager) discuss a growing challenge in mining: resource models are getting bigger and bigger. More blocks, more attributes, more simulations. While this can improve geological representation, it can also slow down optimisation, scheduling and everyday planning decisions. So how do we strike the right balance between detail and usability? Jamie and Tarrant explore why models are expanding, the practical consequences for engineers, and how geologists and planners can work together to build fit-for-purpose models that support better decisions without unnecessary complexity.  Key moments in this episode 00:00 Introduction: Why resource models keep getting larger 03:40 The three main drivers of model size 07:10 How large models slow optimisation and planning workflows 09:30 When higher resolution models are actually justified 14:20 Practical ways to reduce model size without losing value 20:00 Strategies engineers use to simplify models for optimisation 24:55 The key takeaway: the best model is not the biggest model  If you work with block models, resource estimation, or mine planning, this conversation highlights practical ways to improve workflow efficiency while maintaining the geological detail that matters.  If you would like to contact Tarrant and Jamie: contact(at)snowdenoptiro.com 🎧 Fresh Thinking by Snowden Optiro is rapidly becoming the best mining podcast globally, and is available as an audio podcast on all major podcast platforms, and in video format on Snowden Optiro's YouTube channel. Snowden Optiro: Snowden Optiro is a resources consulting and advisory group that provides independent advice, consulting and training to mining and exploration companies, their advisors and investors. We help mine developers to advance their projects, mining companies to improve their operations and their professionals, and investors to de-risk their investments by the provision of quality advice, training and software in the field of Mineral Resources and Mineral/Ore Reserves. Explore more: https://snowdenoptiro.com/

In this episode of Fresh Thinking by Snowden Optiro, our General Manager Dr Tarrant Elkington speaks with Senior Consultant Dr Gregory (Greg) Zhang about a common question in the mining industry: what is the real industry standard in mineral resource estimation? Drawing on experience reviewing projects across a range of commodities and deposit types, Greg discusses current practices in data management, QAQC, geological domaining, estimation methods such as kriging, and resource reporting. The conversation also explores how practices are evolving and the emerging role of simulation methods and machine learning in resource estimation. Key topics: 00:01 – Introduction and the motivation behind the study 03:30 – Data quality and common database issues 07:20 – QAQC and confidence in data 10:30 – Geological domaining and understanding deposits 16:20 – Estimation methods and industry trends 20:10 – Resource reporting and common pitfalls 25:00 – Future trends in resource estimation If you would like to contact Tarrant and Greg: contact(at)snowdenoptiro.com 🎧 Fresh Thinking by Snowden Optiro is rapidly becoming the best mining podcast globally, and is available as an audio podcast on all major podcast platforms, and in video format on Snowden Optiro's YouTube channel. Snowden Optiro: Snowden Optiro is a resources consulting and advisory group that provides independent advice, consulting and training to mining and exploration companies, their advisors and investors. We help mine developers to advance their projects, mining companies to improve their operations and their professionals, and investors to de-risk their investments by the provision of quality advice, training and software in the field of Mineral Resources and Mineral/Ore Reserves. Explore more: https://snowdenoptiro.com/

In this episode of Fresh Thinking, Susan Havlin (Managing Consultant APAC) speaks with Dr Gregory Zhang (Senior Consultant APAC) about using Excel as a transparent learning environment for geostatistics. Rather than relying on black-box software, they explore how building the logic step by step in a spreadsheet can strengthen intuition, improve data discipline and deepen technical confidence. Whether you are a geologist, resource modeller or mining professional wanting to better understand what sits behind the software, this episode breaks down the thinking that underpins robust estimation. 🔎 In this episode: 00:01 – Why the Excel World Championship is more relevant to geologists than you might think 02:02 – Why Excel is a powerful tool for learning geostatistics 06:27 – Building variograms from scratch: pairs, distances and continuity 09:24 – Understanding kriging as a system of equations 12:03 – Simple validation routines to keep yourself honest 13:02 – Can Excel help you understand machine learning? If you want to move beyond "clicking the kriging button" and truly understand the mechanics behind resource estimation, this conversation is for you. If you would like to contact Susan and Greg: contact(at)snowdenoptiro.com 🎧 Fresh Thinking by Snowden Optiro is available as an audio podcast on all major podcast platforms, and in video format on Snowden Optiro's YouTube channel. If you need further assistance in using Excel, we have 2 courses that might interest you: 1-day Essential Excel Skills for Geologists and our 1-day Advanced Excel Skills for Kriging & Simulation. Both courses are presented by Dr Gregory Zhang. Link to training courses: https://snowdenoptiro.com/professional-development/ Listen on the go: Fresh Thinking by Snowden Optiro is rapidly becoming the best mining podcast globally, and is available on all major podcast platforms. Snowden Optiro: Snowden Optiro is a resources consulting and advisory group that provides independent advice, consulting and training to mining and exploration companies, their advisors and investors. We help mine developers to advance their projects, mining companies to improve their operations and their professionals, and investors to de-risk their investments by the provision of quality advice, training and software in the field of Mineral Resources and Mineral/Ore Reserves. Explore more: https://snowdenoptiro.com/

In this episode of Fresh Thinking, Ian Glacken (Executive Consultant) and Dr Gregory Zhang (Senior Consultant) discuss one of the most important topics in modern resource modelling: uncertainty. From the long-standing debate of simulation vs estimation, to the growing focus on geological uncertainty and hierarchical truncated plurigaussian simulation, this episode explores where the mining industry stands — and where it still needs to improve. ⏱ Key Topics 00:00 – Introduction: Simulation in mining and why uncertainty matters 01:18 – Simulation vs estimation: what's the real difference? 02:16 – The "space of uncertainty": grade, geology, parameters and planning 03:34 – Are we misleading stakeholders by ignoring uncertainty? 05:34 – Has grade uncertainty been solved? Two-point vs multipoint simulation 06:39 – Data uncertainty: blast holes, nugget effect and sampling quality 07:30 – Parameter uncertainty and spatial bootstrapping 09:43 – Geological uncertainty: why it's fundamentally different 10:44 – Plurigaussian and hierarchical truncated plurigaussian simulation (HTPGS) 12:51 – Industry adoption and emerging trends 13:08 – The "holy grail" of a comprehensive uncertainty model 14:47 – Digital twins and the future of integrated uncertainty modelling 👍If you enjoyed this discussion, please Subscribe to Fresh Thinking wherever you listen to podcasts, for more mining-focused technical discussions across the mine value chain. If you would like to contact Ian Glacken and Dr Gregory Zhang: [email protected] Listen on the go: Fresh Thinking by Snowden Optiro is rapidly becoming the best mining podcast globally, and is available on all major podcast platforms. It is also available in video format on Snowden Optiro's YouTube channel: https://youtu.be/-DnskmSDnn4 Snowden Optiro: Snowden Optiro is a resources consulting and advisory group that provides independent advice, consulting and training to mining and exploration companies, their advisors and investors. We help mine developers to advance their projects, mining companies to improve their operations and their professionals, and investors to de-risk their investments by the provision of quality advice, training and software in the field of Mineral Resources and Mineral/Ore Reserves. Explore more: https://snowdenoptiro.com/ #Mining #ResourceModelling #Geostatistics #Simulation #Geology #MiningEngineering