  Complex fluids exhibit a variety of exotic flow behaviours under high
stresses, such as shear thickening and shear jamming. Rheology is a powerful
tool to characterise these flow behaviours over the bulk of the fluid. However,
this technique is limited in its ability to probe fluid behaviour in a
spatially resolved way. Here, we utilise high-speed imaging and the
free-surface geometry in drop impact to study the flow of colloidal
suspensions. We report, for the first time, observations of coexisting solid
and liquid phases due to shear jamming caused by impact. In addition to
observing Newtonian-like spreading and bulk shear jamming, we observe the
transition between these regimes in the form of localised patches of jammed
suspension in the spreading drop. We capture shear jamming as it occurs via a
solidification front traveling from the impact point, and show that the speed
of this front is set by how far the impact conditions are beyond the shear
thickening transition.
