Crystal–chemical systematics of lithium in minerals: A tool for future positive mining

Lithium is a critical resource for the transition to green technologies, in particular for battery production. Commercially sourced lithium originates from both natural brines (e.g. LiCl), and mineral ores such as spodumene (LiAlSi2O6), amblygonite ((Li,Na)AlPO₄(F,OH)), petalite (LiAlSi4O10), and lepidolite (K(Li,Al)3(Si,Al)4O10(F,OH)2). With the increasing demand for lithium, minerals are receiving increasing attention for securing resources and value-chains for this critical element due to their faster processing times. To ensure cost-effective lithium extraction, minerals with high lithium content are favoured, necessitating a particular crystal-chemistry that favours lithium over other competing cations, such as aluminium, sodium, and potassium.  However, quantification of lithium in minerals is particularly challenging, hindering structural–chemical relationships in lithium bearing minerals that could provide insight into lithium mobility and cycling through geological time, as well as mineral vectoring and resource discovery. 
In this project, the student will make use of the extensive lithium mineral collection at the Natural History Museum to systematically characterise their lithium abundances, coordination environments, crystal-chemistry and thermal properties, using single-crystal and neutron diffraction techniques as well as ‘light-element’ specific X-ray spectroscopy methods at synchrotron facilities. This study aims to quantify the structural and electronic environments of lithium ions incorporated within different mineral families, thereby elucidating structure–chemical–property relationships when lithium is present as either a major or minor component.