PhotonAssay™: A Review of Real-World Performance on Heterogeneous Gold Ores
DOI: 10.62178/sst.005.007
Abstract
PhotonAssay™ is a non-destructive gold assay method based on gamma activation analysis which has been applied extensively across a wide range of gold ore types. This paper reviews real-world performance on heterogeneous ores, with emphasis on method comparison, sampling behaviour, and the practical significance of positional heterogeneity. The underlying physics of PhotonAssay™ allows direct measurements on aliquot masses typically an order of magnitude larger than conventional fire assay. Results from certified reference materials, large-scale feasibility studies, and detailed case studies across multiple deposit styles are examined. Across these studies, PhotonAssay™ shows strong agreement with fire assay and measurements on coarse and pulverized materials are consistent, with mean grade ratios generally close to unity and high correlations observed across diverse geological settings. The findings indicate that larger assay masses can reduce total sampling variance relative to conventional small-charge fire assay, particularly in coarse or nuggety ores where sub-sampling error dominates. Although spatial sensitivity variations within the sample jar are physically real, theoretical analysis and empirical evidence show that their contribution to total uncertainty is modest in practical applications. Overall, PhotonAssay™ provides a technically robust and operationally advantageous alternative for gold analysis on heterogeneous ores.
Published in Issue 5 · June 2026
Citing this article
Tickner, J., Chuah, J., Weatherstone, A. & Sennett, T. (2026). PhotonAssay™: A Review of Real-World Performance on Heterogeneous Gold Ores. Sampling Science & Technology, June 2026(5), 76-94. https://doi.org/10.62178/sst.005.007
Copyright
This article is published using the CC BY-SA license. You are free to copy and redistribute the material in any medium or format for any purpose, even commercially and free to remix, transform, and build upon the material for any purpose, even commercially. You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.
If an article includes an image that was used with permission, or as fair use, the CC license will only apply to the author‘s original content, not that image.