This is a project to combine laboratory experiments and numerical calculations to investigate the dynamical interaction of melts and solids in the Earth's core and mantle. The PI will carry out laboratory experiments on thermochemical convection with crystallization in a rotating, electrically conducting fluid with a co-rotating toroidal magnetic field, and apply the results to dynamics in the Earth's core. These experiments will exploit the unique properties of gallium alloys as laboratory fluids for modeling melt-solid interactions in the core.