All stars in the open cluster and Argus association were found to share similar abundances with the scatter well within the uncertainties, where [Fe/H] = -0.04 +/- 0.03 for cluster stars and [Fe/H] = -0.06 +/- 0.05 for Argus stars. Effects of overionization/excitation were seen for stars cooler than roughly 5200 K as previously noted in the literature. Also, enhanced Ba abundances of around 0.6 dex were observed in both systems. The common ages, kinematics and chemical abundances strongly support the fact that the Argus association stars originated from the open cluster IC 2391. Simple modelling of this system finds this dissolution to be consistent with two-body interactions.