Author Description

The method of analysis described is applicable to samples of activated charcoal with a gold concentration of 15 g/t and higher. The use of a loose-powder technique minimizes the time taken for the preparation of samples. A platinum internal standard is used for the correction for matrix effects and for differences that could be caused by the packing of the loose charcoal into liquid-sample cups. The precision of the method ranges from a relative standard deviation of 0,085 to 0,016 for concentrations of gold from 67 to 3800 g/t respectively. The agreement between the recommended values for a set of reference samples and the values obtained by the X-ray-fluorescence method is better than 3 per cent. The overall time required for the analysis of ten samples and standards is approximately 1 hour. A detailed laboratory method and a computer programme for the calculations are given as appendices.