1887
2nd Australasian Exploration Geoscience Conference: Data to Discovery
  • ISSN: 2202-0586
  • E-ISSN:

Abstract

Summary

The Chrysos PhotonAssay™ Max is an instrument utilising high-energy X-rays but reimaged for the modern world with full robotics and ability to keep up with the high demands of mining. Since Pierre Gy’s introduction of sampling theory into the gold mining industry, many researchers have struggled with limitation of the available techniques, like fire assay and cyanide leach, and their impact on the fundamental errors in relating the assay value to the drill hole or deposit. Gold provides some unique sampling challenges over other commodity elements as it is malleable and is difficult to homogenise by pulverisation.

By analysing a sample size 10 times that of a traditional fire assay, the sample variance is often decreased providing immediate benefit to the geologists, as predicted by sampling theory. By reducing the sample preparation down to the 3 mm crush, there is also an immediate benefit in cost and time savings. Statistical tests show that the analysis on the 3 mm product size by PhotonAssay™ is similar to the traditional analysis by fire assay, suggesting the two techniques can be used interchangeably during a drilling program. This paper describes some of the tests we have done to give the industry confidence that this technique provides immediate benefit and can be used to compare to historical fire assay data.

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/content/journals/10.1080/22020586.2019.12073071
2019-12-01
2026-01-19
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References

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  10. Minitt, R.C.A, Rice, P.M., and Spangenberg, C. “Part 2: Experimental calibration of sampling parameters K and alphafor Gy’s formula by the sampling tree method”, JSAIMM, 2007, 107, p513-518
  11. Minnitt, R.C.A and Assibey-Bonsu, W. “A comparison between the duplicate series analysis method and the heterogeneity test as methods for calculating sampling constants, K and alpha” JSAIMM, 2010, 110, p251-268
  12. J. Tickner, B. Ganly, B. Lovric, J. O'Dwyer (2017). Improving the sensitivity and accuracy of gamma activation analysis for the rapid determination of gold in mineral ores. Applied Radiation and Isotopes, 122, p28-36.
/content/journals/10.1080/22020586.2019.12073071
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  • Article Type: Research Article
Keyword(s): gold; sampling
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