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Critical mineral lithium—the lightest of all metals—had long eluded geologists by slipping through the cracks of traditional analysis.

Its low atomic weight, the very trait that makes it ideal for powering electric vehicles or renewable energy storage, made it difficult to detect in drillcore samples. This changed when laser-induced breakdown spectroscopy (LIBS) first became available as a tool in the 1960s.

Now thanks to advances in portability and speed, LIBS can be used in the field to create mineral maps of lithium as well as other light metals.

LIBS is a powerful, complementary tool for greenfields exploration through to downstream processing. And while there is continued growing interest in using LIBS for lithium characterization, its benefits go beyond.

The technology is breaking ground in mining more broadly by enabling fast analysis of more drillcore samples across commodities, without compromising on elemental data quality. From gold and copper to nickel and graphite—LIBS can be used on any mineral system and on any drillcore or chip.

Real-time data for processing plants

According to Geoscience Australia, about were collected for green- and brownfields exploration in Australia in 2024. But only a fraction of these go on for detailed analysis. Benefits have mostly been realized upstream to date. The costs and time to get assay results are generally incompatible with the day-to-day pressures of continuous mine operations.

Traditionally geologists have trained their eye to look for certain characteristics in rocks, either analyzing the drillhole or selecting a core sample about every 20 meters to be cut and sent to laboratories for analysis. But it can then take two to three months to receive assay results.

LIBS is the only field-portable tool that can directly analyze lithium. Instant analysis results can help to quickly close decision-making loops. Faster, more targeted exploration means less unnecessary drilling and more efficient resource use.

CSIRO's Minerals Systems scientist Dr. Adam Bath said instant results could also benefit processors downstream across commodities.

"In Australia, it's feasible to extract minerals equivalent to the size of a golf ball from an entire truckload of rock," Dr. Bath said. "But there can be other deleterious elements or minerals in the rocks that can cause huge problems in processing downstream.

"By mapping the minerals, metallurgists can know exactly what rocks are being crushed up and sent from the mill so they can adapt their processes accordingly."

LIBS would provide real-time data to inform decision-making, help processors plan ahead and reduce risks of errors and inefficiencies.

The beaming genius of laser analysis

LIBS' key advantages over other analysis tools are speed, portability and minimal preparation time.

CSIRO physicist Dr. Jamie Laird said LIBS uses a high-pulse energy laser to ablate a drillcore sample.

"The ablation process breaks down tiny particles from the rock's surface into a gas or vapor known as plasma.

"As the plasma cools down, it emits light with wavelengths—also known as spectral 'fingerprints'—that indicate the elements contained."

It's faster than traditional technology, such as Scanning Electron Microscopy (SEM). LIBS produces immediate results versus months-long lag times. And it works on fairly flat surfaces, so costs upward of $1,000 can be saved on preparation alone.

Rapid results in the field

LIBS comes in handheld devices through to more powerful photocopier-sized machines, making it easily scalable.

However, there are disadvantages as CSIRO geologist Dr. Nick Farmer explained.

"When we look at analytical tools, there are tradeoffs between speed, scale and precision, particularly at the micron level," Dr. Farmer said.

"LIBS doesn't achieve the same detailed accuracy as SEM, and the data are much harder to interpret than X-Ray fluorescence (XRF).

"LIBS can be used to create mineral maps on vastly more samples than SEM, and it can see light elements like lithium that are invisible to XRF. But it's best used in conjunction with them on complex mineral systems."

CSIRO offers an array of analytical tools via its Geoscience Drill Core Laboratory.

As part of this suite, Dr. Farmer and Dr. Laird are working on developing LIBS systems with more intense lasers.

"We're developing a next-generation LIBS system in-house with much more intense laser pulses to enhance elemental composition detail. It will be a lab-based instrument that we hope to adapt for mine sites down the track."

Ensuring results are rock solid

CSIRO is also working on a training data library that uses machine learning to enhance the LIBS technique. The library brings together drillcore data from the Yilgarn goldfields, as well as lithium deposits.

"We're scanning a large representative suite of mounts from CSIRO's extensive collection—which includes over 25,000 samples—to build a comprehensive reference library for validating LIBS results," Dr. Bath said.

"Ultimately, this database can help us to scale LIBS technology across industry. We hope to build similar databases with mine sites around Australia."

From space to the underground

LIBS is being used right across materials science, from minerals to pharmaceuticals, archaeology and space exploration. Most famously, NASA's Mars Rover deployed LIBS technology in space to identify different minerals on Mars.

Given its ruggedness and suitability for different atmospheres, our scientists will next test it in new frontiers underground. In collaboration with CRC ORE, CSIRO is leading groundbreaking research to send a LIBS device down a drillhole.

It's new and challenging work due to the inherent uncertainties in going underground. For example, encountering groundwater would potentially impact LIBS' effectiveness. The research aims to overcome these obstacles and demonstrate how the industry could access near-real-time data direct from the source.

For now, there are more immediate plans to embed LIBS in minesite laboratories.

And it couldn't come at a more critical time. As a leading mineral producer, Australia can reap major efficiencies from LIBS across the value chain.