Mineralogical investigation of Chumbalak Pegmatites in Eastern Afghanistan Kunar province Chapadara

Abstract

Pegmatites represent a significant magmatic or segregated rock unit that constitutes a critical host for precious gemstones and rare-metal mineralization, rendering them a principal focus of economic geology research. This investigation presents a petrographic characterization of pegmatite bodies within the Chumbalak area, Darah Pech District, Kunar Province, eastern Afghanistan. Field reconnaissance confirmed the presence of numerous pegmatite veins, from which 5 representative samples were collected, comprising 3 from pegmatite bodies and two from the adjacent country rock. Petrographic analysis identifies quartz, K-feldspar, plagioclase, and mica as the dominant mineral assemblage, confirming the pegmatitic texture and composition, also accessory phases, notably schorl (Fe-rich tourmaline), muscovite, and biotite. Geochemical data indicate that the pegmatites were derived from the crystallization of residual, highly fractionated acidic melts. The enrichment of incompatible elements within these differentiated melts is consistent with their role as a source for rare-element mineralization.