Duplicate Sample Analysis

Duplicate samples measure the precision and reproducibility of sampling and analytical procedures. Types of Duplicates Field Duplicates Second sample collected from same location. Measures sampling precision. Coarse Duplicates Split from coarse reject at laboratory. Measures preparation precision. Pulp Duplicates Split from pulverized sample. Measures analytical precision. Evaluation Methods Half Absolute Relative Difference HARD HARD = |Original - Duplicate| / Original + Duplicate / 2 × 100% Acceptable HARD values: - Precious metals: <10-15% - Base metals: <15-20% Thompson-Howarth Plots Plot original vs. duplicate values to visualize precision.

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Previous lesson: Implementing Blanks and Standards — Proper insertion and evaluation of blanks and standards is critical for data quality. Blank Sample Protocol Material Selection - Use certified barren…
Next lesson: Chain of Custody — Chain of custody documentation tracks samples from collection through final assay reporting. Purpose - Prevent sample tampering or loss - Enable audit…

Verification resources

Cross-check terminology, classification, methods, and safety with these authoritative external resources.

Mineral Exploration Best Practice Guidelines — Canadian Institute of Mining, Metallurgy and Petroleum. Professional guidance for representative sampling, chain of custody, laboratories, security, and QA/QC.
National Instrument 43-101 — British Columbia Securities Commission. Canadian mineral-project disclosure requirements and related technical-report framework.

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Duplicate Sample Analysis

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Verification resources