In this video Lynda Bloom discusses why homogeneity is important and why some manufacturers find it difficult to achieve good homogeneity in gold standards (certified reference materials).
A look at 5 key things to look for when choosing a CRM supplier that maximise your chance of a successful quality control program.
A short video about key concepts of quality control for mineral exploration
Abstract
All resource models depend on assays and an assumption that representative subsamples were assayed accurately. Resource estimation, for gold projects in particular, requires an understanding of routine sample preparation and assay methods.
Assay quality control programs have become near ubiquitous since NI43-101 reports were introduced nearly 20 years ago. There are no specific rules for the rate of insertion, actions required for quality control failures and other questions that frequently arise. Statistics from studies of publicly available NI43-101 reports will be presented that have helped Analytical Solutions Ltd. develop guidelines for clients to achieve “industry standard” compliance.
Achieving a representative sample for assay is a significant challenge for some gold projects. Part of the challenge is balancing the cost of sample preparation and maximizing the probability of achieving a representative sample. Justifying higher costs for sample preparation should be based on duplicate data and the correct estimation of precision. The industry uses a wide range of statistics to estimate precision; this has caused confusion about optimum results.
The preferred methods of calculating precision using the coefficient of variation and visualization of the data are presented.
The focus of this paper is the control and improvement of analytical data quality for exploration geochemical surveys. Many types of geochemical surveys (hydrogeochemistry, biogeochemistry, selective extractions and rare earth lithogeochemistry) take advantage of modern technology, such as ICP-MS, and require measurement of elements at the sub-ppb level.
This third edition expands the original mandate of surficial geochemical reports to include multiple types of geochemical surveys with survey-specific recommendations.
Edited by Lynda Bloom and Owen Lavin.