Petrology of ijolite xenoliths entrained in a nephelinite dyke from the Kamthai, Late Cretaceous polychronous Sarnu-Dandali alkaline complex, North-West India: Evidence for recurrent magmatic pulses and magma mixing

•First report of ijolite xenoliths in nephelinite dyke.•A heterogeneous population of pyroxenes pointing to magma mixing.•Presence of multiple magma chambers in a complex plumbing system.•Perovskite oxy barometry reveals the fugacity conditions of the magma.