Chapter 4 - Sampling Procedures

Abstract

Correct sampling and sample preparation practices are critical to obtaining meaningful analytical data in the gold industry for the accurate delineation of ore resources, metallurgical accounting, and the evaluation and control of mining and processing operations. The basic rule for correct sampling and sample processing is that all parts of the ore, concentrate, or slurry being sampled must have an equal probability of being collected and becoming part of the final sample for analysis. If this is not the case, bias is easily introduced that cannot be eliminated by simply averaging replicate measurements, and the entire measurement chain is corrupted at the outset. Clearly, there is little point in using the latest analytical methods and equipment and spending considerable time and effort estimating resources or attempting to reconcile production figures if the samples presented for analysis are not representative in the first place. Consequently, sampling and sample preparation need to be given the attention they deserve as the first critical steps in the measurement chain. Special care must also be taken to ensure that sample masses are adequate at each stage of sampling and sample preparation to achieve the required precision.