A surface scanning technology from Mars missions: Laser-induced breakdown spectroscopy (LIBS)

As climate change accelerates, exploration firms and global miners face mounting pressure from two directions. On one side, shareholders, as well as some policymakers, want them to accelerate the pace at which they can efficiently identify and then bring critical minerals to the market. On the other, regulators, non-governmental organizations (NGOs), and ESG-oriented institutional investors increasingly expect miners to devise new ways to minimize mine footprints, optimize on-site energy consumption, reduce chemical use, and mitigate the environmental impacts of tailings. Both types of stakeholders are motivated by a desire to accelerate the energy transition and reduce carbon emissions in the wider economy by driving mining productivity through innovation.

Despite advances in exploration technologies aimed at identifying mineral deposits, the processes for testing core samples remains cumbersome and still relies, in many cases, on hand-logged entries by geologists as well as chemical assays that must be conducted in off-site laboratories. The industry routinely uses mineral classification imaging techniques, such as X-ray fluorescence spectrometry and infra-red hyperspectral imaging, but these can also be time-consuming and are not effective with lighter elements, including lithium.

Laser-induced breakdown spectroscopy (LIBS) has emerged in the past decade as a compelling alternative. Conceptually, the surface of a core sample is ablated with laser pulses while a spectrometer takes readings from the resulting plasma emissions. As the plasma cools, the optical device records the distinct spectral fingerprints for every element contained within the ablated portion of the sample, creating a rapid and highly granular in situ mapping of the mineral composition of the sample.

In the past decade, research-oriented applications for LIBS involved the deployment of a non-commercial LIBS system on the Mars Curiosity mission in 2012. The rover used these devices (dubbed ChemCam) to evaluate the mineral composition of surface rocks without physically collecting samples. Other non-mining applications include the mapping of shale cores for unconventional oil and gas reserves.

Relying on peer-reviewed testing that has confirmed the accuracy of LIBS relative to predecessor technologies, several firms have developed and commercialized handheld LIBS analyzers for use in field prospection work. They provide advantages and precision not found in other field portable technologies. However, for core logging and exploration, handheld LIBS serve primarily as support tools. They remain labour intensive and prone to certain shortcomings, such as the need for frequent cleaning of the window on the laser aperture.

Elemission’s ECORE systems have significantly advanced the use of LIBS mineral analysis across the entire spectrum of mining activity, from prospection and exploration to exploitation, remediation, and environmental monitoring. The three ECORE models (full-scale and two portable versions, one of which is deployed to the field in a modified shipping container) automate the process, enabling larger quantities of samples to be analyzed rapidly. They use machine learning (ML) software to achieve further accuracy in mineral characterization across the full table of elements while substantially accelerating the number of readings to 2000 per second — a critical feature that enables our system to analyze kilometres of core.

ECORE’s combination of automation, artificial intelligence (AI), and speed gives miners a tool that can be used to calibrate the grinding/flotation processes and thus optimize the recovery of marketable minerals, including Cu, Li, Au, Zn, and more. Ultimately, ECORE’s automation features eliminate the risk of isolated human error, and, unlike handheld LIBS devices, provide users with accurate mineralogy.

Case studies

In 2020, we reported on the results of a side-by-side test comparing Elemission’s first commercial LIBS analyzer, CORIOSITY, with a scanning electron microscopy analyzer paired with energy-dispersive X-ray spectroscopy (SEMS-EDS) — a mature technology. The goal of the published study was to assess LIBS performance against a commercialized mineral surface mapping device (TIMA-X), using core samples from the platinum group of elements (PGE) — a family of scarce minerals with applications in a broad range of domains, including chemotherapy drugs, energy catalysts, and consumer electronics such as storage devices and smartphones.

The TIMA-X analyzer required highly polished samples and a controlled laboratory environment whereas CORIOSITY is designed to scan larger quantities of samples that do not require time-consuming preparation. Our machine, moreover, was engineered to operate in harsh field conditions and does not require special devices such as pumps and gases other than air or exhaust fans. These features are intended to reduce the time and cost associated with traditional mineralogy technologies.

The results of our study showed that CORIOSITY’s rapid LIBS surface analysis yielded comparably precise core sample scans to the more established SEMS-EDS machine, even one that has been re-engineered to increase scan speeds. As demonstrated by the implementation of the extra-terrestrial mining application of the ChemCam instrument on Mars’s Curiosity rover since 2012, our study demonstrated that LIBS is a valuable tool for surveying the landscape or orebody samples rapidly to quickly converge to high-value samples that require deeper investigation with complementary analytical approaches.

We subsequently demonstrated that the well-established micro-X-ray fluorescence technique validated LIBS data gathered from two other PGE samples. The study demonstrated the ability of the LIBS technique to perform direct fast high-resolution mapping of the chemical and mineralogical composition of PGE ore samples.

A related insight about the utility of LIBS analysis is that the accuracy of the scan provides critical information about the concentration and structure of both the target mineral and other minerals in the orebody, such as high levels of iron sulfates that contaminate the concentrates. That granular data, which can be collected rapidly in the field, allows miners to precisely calibrate the milling process to avoid grinding the ore more than necessary, thus saving energy and reducing operating expenses.

Additionally, the pace of the LIBS processes relative to mature technologies, when deployed across the entire mine lifecycle, enables miners to pivot more rapidly from exploration to exploitation to remediation. The accelerated speed helps address the questions of social acceptability that miners routinely encounter when permitting new mines.

Since publishing these results, we have launched a commercial-scale pilot project, deploying ECORE, which is an enhanced version of CORIOSITY, to analyze pre- and post-treatment ores, with the goal of adjusting the grinding/flotation processes to minimize the amount of saleable minerals in the tailings stream. Elemission is working with Vancouver-based Foran Mining on a commercial-scale partnership at the company’s 100%-owned McIlvenna Bay project in Saskatchewan, currently under construction. According to Foran, the licensed 209-km2 site has indicated reserves of 39 Mt, including 1.03 billion lbs of Cu and 1.9 billion lbs of Zn, grading at 2.04% Cu equivalent.

The mine will become the first carbon-neutral facility in Canada and is supported by a $41 million grant from the federal Strategic Innovation Fund, which promotes the adoption of clean and innovative technology. The project funding will support an all battery electric vehicle (BEV) fleet, ventilation on demand, and water-recycling, among other carbon reduction measures.

Over 12 weeks, the ECORE module scanned about 17,254 metres of drill core, and the highly granular mineral characterization maps will be transformed into digital twins, thus providing Foran with an unprecedented map of alteration and ore mineral distribution across the orebody. This body of data can be leveraged to optimize the yield by directing excavation operations to the most mineral dense regions. The ECORE’s ability to rapidly scan very large quantities of drill core has the potential to assist with the planning and engineering processes for deposits such as McIlvenna Bay, which are nearing production. (According to Foran, the project, as of February 2025, remains on schedule to start hot commissioning in H2 2025 and commercial production in H1 2026. The main critical path activities include installation of the primary structural steel and cladding for the mill, installation of the SAG mill and Ball mill, installation of the paste plant, installation of copper and zinc flotation circuits, and commissioning and ramping up to commercial production.)

As Johan Krebs, Foran’s principal Geoscientist, Orebody Knowledge, said of ECORE’s technology, “The new LIBS systems bring the speed up to a place where that was not imaginable just five years ago. Paired that with incredibly well-developed software, it is the synergy of the parts and the knowledge built around this technology that makes ECORE so different. It is only a matter of before the market notices it and latches on that there is something unique here.”

Conclusion

Over the past decade, theoretical and field testing of LIBS systems has demonstrated that an innovative surface scanning technology pioneered in space missions can bring both precision and accuracy to the process of assessing the commercial viability of an orebody. The combination of laser ablation, spectroscopy, and ML enables geologists and metallurgists to rapidly build a location-specific database of a wide range of on-site elements, thereby accelerating the permitting and financing stages of mine development and later optimizing the exploitation of a site. LIBS scanning further holds out the potential for reducing the loss of commercially viable minerals during the grinding/flotation stages to the tailings stream, which is a feature that can assist with remediation while increasing the yield of a mine property. Similarly, this technology allows miners to identify in advance the presence of a range of other metals and minerals that will affect the toxicity of tailings to assist with treatment and remediation.

Taken together, these features of LIBS-based analysis can provide substantial productivity improvements at all points on the mining life cycle, from exploration to remediation. 

Elemission’s CEO François Doucet holds a Ph.D. and a master’s degree in analytical chemistry from the Université de Montréal and has 26 years of expertise in LIBS. He is a subject-matter expert in atomic emission, laser ablation, spectroscopy, chemometrics, nuclear forensics, and process chemistry.