Application of portable delayed neutron activation analysis equipment in the evaluation of gold deposits

Abstract

The attributes of a gold analysis system which could act as a panacea for the needs of the explorationist and the miner alike would include: i) The capability of being used as a qualitative as well as a quantitative tool yielding accurate results in respect of large samples. ii) The capability of generating results on site either in the field or within a prospect or mine. iii) An identifiable cost effectiveness in relation to other methods. iv) The capability of being housed in an equipment package which combines ruggedness, portability and reliability with operational options which permit measurements to be made on outcrops, mine faces, borehole cores as well as direct in-situ down-the hole determinations. The portable x-ray fluorescence gold analyser is on the threshold of meeting all the criteria cited above. Since the system is non-destructive in so far as the sample is concerned check assays employing conventional techniques can be run on a small percentage of the sample population. This report by its very nature is a state of the art review which sets out to describe the current instrument package, the principles by which it functions, its performance compared with detailed chip channel sampling and then suggests how the system may evolve in terms of its application to the investigation of hard-rock and placer deposits.Introduction -- Development of the gold analyser -- Basic principles of the system -- The instrument package -- Hand held probe -- Electronic pack -- Control module -- Liquid nitrogen supply -- Operational safety -- Review of operating results -- Sampling practice -- Broader applications -- Conclusions and recommendations -- Costs -- Acknowledgements -- Appendixes 1 and 2 -- References and information sources