Geochronology and source of the rare-metal pegmatite in the Mufushan area of the Jiangnan orogenic belt: A case study of the giant Renli Nb–Ta deposit in Hunan, China

•Nb–Ta mineralization age of the Renli deposit is 133.0 ± 2.6 Ma.•The granitic wall rock of rare metal pegmatites formed during 141–138 Ma.•The rare-metal pegmatite and granite were sourced from the Lengjiaxi Group strata.•Jiangnan orogenic belt was in a subduction setting in the Early Cretaceous.