SAMPLING , ANALYSIS AND LAB ASSAY
Large commercial laboratories such as MSALABS have bought into the benefits of using Chrysos ’ PhotonAssay technology
“ Second , it means that for every unit around the world , we are physically responsible for the maintenance of the technology . This ensures all our units operate in the same way and the users do not need to employ technicians for PhotonAssay-specific maintenance .
“ And third , as our customers typically sign up on a ‘ number of samples ’ basis , we always have opportunities for further agreements / deployments . Considering we ’ re working with three of the big four laboratories and some of the major gold miners , the potential for increasing the size of these orders is high .”
Since becoming a public entity with its listing on the Australian Securities Exchange in 2022 , Chrysos has been quoting a total addressable market ( TAM ) of 610 PhotonAssay units to investors .
When stacked up against the 21 units it plans to have deployed by the end of June 2023 , its current manufacturing capacity of 12 units a year and its 18 unit / y facility expansion potential , the Chrysos team have focused on addressing the highest-value opportunities within this pipeline .
“ Even at a production rate of 18 units a year , we ’ re talking about 30-something years before we dominate the market ,” Treasure said . “ As a result , we ’ re not just looking to grow the TAM ; we ’ re looking at ways to maximise the opportunity within the existing market .”
Some of the more obvious inroads include deployments where PhotonAssay can measure not only gold , but also copper and silver – like the company is doing for Barrick in Tanzania – in addition to bolting moisture analysis onto existing remits .
Potential moves into analysing other “ complementary elements ” to copper , like molybdenum , lead and zinc , could further drive PhotonAssay use in certain applications .
“ There is some other cool stuff we are doing on heterogeneity analysis ,” Treasure offered up . “ We get a lot more detail out of our samples than just gold assays and , as a result , we are seeing customers try things that would usually be deemed economically unfeasible with other techniques , such as running drill holes to extinction to obtain more information about the ore and the gold grade in those samples .”
The development of the company ’ s PhotonAssay ATOM unit – which currently resides at Bureau Veritas ’ lab in South Australia – is another key part of the company ’ s value-adding plans .
Treasure describes this prototype unit as a “ test bed ” for all learnings the company has made since deployment of its first PhotonAssay Max unit .
“ It is all about exploring how we can do things better , what we can integrate into a PhotonAssay system and how we can help facilitate the operator throughout ,” he said .
Factors like mass , fill and recycling of reference materials are all internalised in this prototype unit as part of a mine site deployment setup .
While a mine site is as far away as one could be from the clinical nature of a laboratory , Treasure can see such a mine-ready unit providing transformational value across the sector .
He explained : “ If you ’ re 500 m down a hole and you want to know if you should keep on drilling , what could you do if you had a PhotonAssay unit parked up on site ? You could get a quantitative result in less than 10 minutes allowing you to verify if you need to change direction , keep drilling or stop the hole where it is .
“ ATOM exists to start answering all those questions .”
The company is now assessing what type of physical environment would be required to facilitate such analysis in the field and the possibilities for designing future units to perform these tasks .
With the building of the first prototype PhotonAssay Max unit having occurred more than 10 years ago , the technology is already enabling mining companies and consultants to re-evaluate some of the more fundamental processes the industry has taken for granted , according to Treasure .
“ When sending a sample for analysis , there is an industry assumption that the analytical precision associated with that analysis is the overall precision of your analysis ,” he said . “ The thinking goes : fire assay has a ± x , or PhotonAssay has a ± x , so my result is ± x .
“ What we have found is that the error involved in sub sampling and getting to the requisite sample to run your analysis often significantly exceeds that of the analytical technique itself ,” Treasure said .
He advocates for more sampling , bigger subsamples and consistent sampling processes to get as close to the ‘ truth ’ as is possible in the mining world , with PhotonAssay ’ s substantially larger sample size ( 500 g compared with 30-50 g used in fire assay ) going a long way to addressing this .
Lab-quality geochem analysis in the field
For companies operating in rare earth element ( REE ) exploration and mining worldwide , the accuracy of geochemical analysis is critical to assess the viability of deposits , respectively targeting REE-rich areas for extraction .
In 2021 , the Thermo Scientific™ Niton™ XL5 Plus handheld XRF analyser was launched , bringing with it “ unprecedented analytical performance and accuracy ” when analysing both light elements and heavy metals , the company said .
Since the launch , the company has devised a Niton XL5 Plus REE mode to provide laboratoryquality geochemical analysis of primary elements and REEs to the field , with test work proving its worth .
The Niton XL5 Plus handheld analyser comes with compact measurement geometry , a 5 W X- ray tube operating up to 50 kV at 100 µ A and down to 6 kV at 500 µ A , and the latest silicon drift detector technology with a large area and graphene window .
“ These integrated features provide optimal performance and unprecedented heavy and light
50 International Mining | FEBRUARY 2023