Pegmatites of the Kalba–Narym Batholith (East Kazakhstan): Origin and Classification

This study investigates the trace-element geochemistry of rare-metal pegmatites from the Kalba–Narym Batholith, Eastern Kazakhstan, to establish geochemical indicators of zonation and subtype differentiation within pegmatite fields. Detailed ICP-MS analyses of muscovite and K-feldspar reveal systematic variations in Li, Cs, Rb, Ta, Nb, P, and Ga contents that reflect progressive melt fractionation during the evolution of granitic magmas. These data allow the identification of four main pegmatite subtypes, including barren, beryl, albite–spodumene, and albite, representing successive stages of LCT (Li-Cs-Ta) pegmatite evolution. Both vertical and lateral geochemical zonation are recognized across the Kalba–Narym Batholith, controlled by magmatic differentiation and volatile enrichment. The results highlight the diagnostic value of trace-element systematics in rock-forming minerals as reliable indicators of fractionation and ore potential, and they provide quantitative criteria for the classification and exploration of rare-metal pegmatites within the Kalba–Narym Batholith.