A method to determine the minimum quantity of ore sample required for laboratory scale study of ore pre-concentration by high voltage pulses

High voltage pulse (HVP) selective breakage followed by screen separation has been shown to have the potential to be used for ore pre-concentration. The effectiveness of HVP enhanced pre-concentration is determined by experimentation. It is important when performing these tests, that the minimum quantity of ore sample required to achieve a statistically consistent HVP pre-concentration result is used. In this study, multiple repeat HVP pre-concentration tests were carried out using three different Cu-Au samples and statistical analysis of datasets created by resampling of real data was then performed. The results demonstrate that the minimum sample size required to achieve a statistically consistent result is ore-dependent, and should be determined for every ore sample prior to HVP pre-concentration characterisation. To evaluate the sensitivity of HVP performance to the variation in sample size, a Sensitivity Index (SI) has been introduced and a mathematical description of the Sensitivity Index is presented in this paper.