Resource Estimation
Block Model Validation: The 7-Step Checklist Before You Sign Off
Swath plots, NN comparison, grade-tonnage reconciliation — the 7-step block model validation checklist every resource geologist should run before CP sign-off.
Posts
Posts
30 articles
Resource Estimation
Drawing the Line: Resource Classification Boundaries on Indonesian Projects
How to draw Measured, Indicated, and Inferred boundaries on Indonesian projects. Not just drill spacing — geological continuity, data quality, and kriging variance.
Data Management
Drillhole Database Management: From Field Log to Resource Estimate
Database structure, version control, audit trails, and common data corruption scenarios. The Indonesian field-camp-to-Jakarta-office workflow and where it breaks down.
Drillhole
Drillhole Spacing for Exploration vs Infill: A Field Guide for Indonesian Deposits
How to set drill spacing for epithermal gold, porphyry Cu, laterite Ni, and sedimentary deposits in Indonesia. When infill drilling earns its cost — and when it's waste.
Geology
Geological Domaining: Splitting Your Deposit the Right Way
When to split domains, how to validate them, and the over-domaining trap. Indonesian epithermal case study showing why vein and halo must be estimated separately.
Geostatistics
Indicator Kriging for Cutoff Grade Decisions: When and How
When indicator kriging beats ordinary kriging, how to build probability maps from binary transforms, and threshold selection for Indonesian gold deposits.
JORC
Reporting Resources in Investor Presentations: What You Can and Can't Say
JORC and KCMI rules for public disclosure in investor presentations. What triggers a material change report, common compliance failures, and what you can't say on slides.
Reconciliation
Resource Model vs Mine Reconciliation: Why Your Model Doesn't Match Reality
Why resource models over- or under-predict at the mill. Reconciliation factors, SMU vs block size, dilution, and the grade-control loop that fixes the gap.
QA-QC
Specific Gravity and Bulk Density: Why Your Tonnage Is Wrong
SG measurement methods, common errors, and why tonnage errors dwarf grade errors. Indonesian nickel laterite case study where SG varied 1.2 to 1.8 across the deposit.
KCMI
KCMI Checklist — 12 Things an Auditor Will Ask
12 questions a KCMI auditor will ask: data validation, QA/QC, variogram, kriging, classification. A practical compliance checklist for Indonesian reporting.
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