Lithium can be found in various geological settings, such as pegmatites, brine deposits, and lithium-rich clays.
Pegmatite is a coarse-grained intrusive igneous rock formed from crystallized magma below the Earth’s crust. Pegmatite lithium deposits, also known as hard-rock lithium deposits, can contain extractable amounts of a number of elements, including lithium, tin, tantalum and niobium.
When using a gamma-ray spectrometer for pegmatite exploration, the goal is to identify areas with anomalous gamma-ray emissions that are indicative of the presence of radioactive elements associated with pegmatite-forming minerals. Pegmatites commonly exhibit higher concentrations of potassium (40K) compared to surrounding rocks. Pegmatites may also exhibit increased concentrations of uranium (238U) and thorium,(232Th) Anomalies of these elements can be used to identify areas with potential pegmatite mineralization.
Australia, the US, Canada, Ireland, Finland and the Democratic Republic of Congo are known to host pegmatite lithium deposits. The top-producing spodumene pegmatite operation, known as the Greenbushes mine, is located in Australia,