An instrumental neutron activation analysis technique has been developed for the determination of As, Au, Ba, Co, Cr, Fe, Hf, Sb, Ta, Th, U, W and Zn in large (10–15 g) geological samples using in-pool irradiation with a SLOWPOKE-2 reactor. The technique allows for the simultaneous irradiation of multiple samples using a neutron flux of between 4·1013 and 8·1013 n·m–2·s–1. The detection limits obtained using the analytical methodology described in this paper are acceptable for exploration geochemistry and the technique has been used to analyze samples collected as part of a metallic minerals survey of Jamaica.