  Gravity can affect colloidal suspensions since for micrometer-sized particles
gravitational and thermal energies can be comparable over vertical length
scales of a few millimeters. In mixtures, each species possesses a different
buoyant mass, which can make experimental results counter-intuitive and
difficult to interpret. Here, we revisit from a theoretical perspective iconic
sedimentation-diffusion-equilibrium experiments on colloidal plate-rod mixtures
by van der Kooij and Lekkerkerker. We reproduce their findings, including the
observation of five different mesophases in a single cuvette. Using
sedimentation path theory, we incorporate gravity into a microscopic theory for
the bulk of a plate-rod mixture. We also show how to disentangle the effects of
gravity from sedimentation experiments to obtain the bulk behavior and make
predictions that can be experimentally tested. These include changes in the
sequence by altering the sample height. We demonstrate that both buoyant mass
ratio and sample height form control parameters to study bulk phase behavior.
