Mathieu Bouffard’s paper, co-authored by Gaël Choblet, Johannes Wicht and myself, just got published in Frontiers in Earth Science. This paper presents some results of a model of purely compositional convection at infinite Schmidt number (no diffusion) in a rotating spherical shell driven by the release of light elements at the lower boundary. This situation is inspired by that of Earth’s core although the present paper does not consider the effect of thermal convection of the magnetic field. One of the results is the self-consistent development of a stably stratified layer at the top of the shell by accumulation of light elements released from the bottom, possibly explaining observations from seismology and geomagnetism. Check it out on the journal’s webpage.