Bulk major and trace element and isotopic composition of volcanic and intrusive rocks from the Macusani Volcanic Field, SE Peru

This dataset provides geochemical analyses of strongly peraluminous volcanic and intrusive rocks from the Neogene Macusani Volcanic Field in southeastern Peru, focusing on the lithium-rich Falchani deposit. Samples were analyzed for major elements using X-ray fluorescence (XRF) after loss on ignition (LOI) determination, and trace elements were quantified using inductively coupled plasma mass spectrometry (ICP-MS). Whole rock isotope ratios were obtained using MC-TIMS (Rb-Sr, Sm-Nd) and MC-ICPMS (Pb). The data characterizes the Falchani deposit's distinctive geochemistry, where lithium ore occurs primarily in tuffaceous mudstone (LIthium-rich Tuff) between two Li-rich volcaniclastic units (Upper and Lower Breccia). The chemical composition of Li-ore units resembles highly evolved peraluminous obsidian glasses and shows characteristics typical of rare-metal granites and Li-Cs-Ta pegmatites. Isotope ratios provide constraints on magma sources and petrogenetic processes in this economically significant lithium province.