Analysis of Li hard rock ores for mining exploration using ARL X’TRA Companion X-ray Diffractometer

Significance of the topic

Lithium hard rock ores such as spodumene, petalite, and lepidolite are key raw materials for the production of lithium, an essential element in rechargeable battery technologies for electric vehicles and portable electronics. Rapid and accurate mineralogical analysis supports efficient extraction workflows, enhances ore grade assessment, and guides processing strategies during exploration and beneficiation.

Objectives and Study Overview

This study demonstrates the application of the Thermo Scientific ARL X’TRA Companion benchtop X-ray diffractometer for quantitative phase analysis of three representative lithium hard rock ores. The primary goals are to identify lithium-bearing minerals, determine their abundance, and calculate the overall lithium content to support exploration and processing decisions.

Methodology and Instrumentation

The methodology combines standard XRD data acquisition with automated Rietveld refinement:

• Sample preparation: Ore samples containing predominately spodumene, petalite, and lepidolite were milled and loaded into backloading holders.
• Data collection: Reflection mode XRD using Cu Kα radiation with sample spinning for 30 minutes per sample.
• Instrument: Thermo Scientific ARL X’TRA Companion equipped with a θ/θ goniometer, a 600 W Cu X-ray source, a solid state pixel detector, divergence and Soller slits for beam collimation, and a variable beam knife to minimize air scattering.
• Data analysis: One-click Rietveld refinement performed in Profex software, with automated phase identification, quantification, and lithium content calculation.

Results and Discussion

Quantitative XRD results reveal the mineralogical composition and lithium content of the samples:

• Sample 1 (high-grade spodumene ore): Spodumene dominates at ~61 wt%, yielding a total lithium content of ~2.5 wt%.
• Sample 2 (petalite-rich ore): Petalite comprises 12 wt% with additional lithium phases, totaling ~0.7 wt% Li.
• Sample 3 (lepidolite-rich ore): Lepidolite and other lithium phases contribute to ~0.7 wt% Li.

Although minor uncertainties arise from solid solution behavior in certain phases, the Rietveld approach provides reliable estimates for ore grading and process optimization.

Benefits and Practical Applications

• Rapid quantification: Automated Rietveld refinement delivers phase composition and lithium content in minutes.
• User-friendly operation: The benchtop XRD design and one-click analysis reduce operator training requirements.
• Process optimization: Mineralogical insights enable targeted beneficiation strategies and real-time grade assessment.
• Facility integration: Seamless data transfer to LIMS supports quality control and decision-making workflows.

Future Trends and Potential Applications

Advances in diffractometer sensitivity and software automation are expected to further accelerate mineralogical screening in exploration laboratories. Integration with machine learning algorithms may enhance phase recognition and prediction of ore behavior. Portable XRD units could enable in-field analysis, speeding up exploration campaigns and reducing sample transport constraints.

Conclusion

The ARL X’TRA Companion XRD, combined with automated Rietveld refinement, offers a robust, efficient approach for the quantitative analysis of lithium hard rock ores. This methodology supports accurate ore grading and process optimization, proving valuable throughout exploration and beneficiation stages.