  We report on the crystallization kinetics in an entropically attractive
colloidal system using a combination of time resolved scattering methods and
microscopy. Hard sphere particles are polystyrene microgels swollen in a good
solvent (radius a=380nm, starting volume fraction 0.534) with the short ranged
attractions induced by the presence of short polymer chains (radius of gyration
rg = 3nm, starting volume fraction 0.0224). After crystallization, stacking
faulted face centred cubic crystals coexist with about 5% of melt remaining in
the grain boundaries. From the Bragg scattering signal we infer the amount of
crystalline material, the average crystallite size and the number density of
crystals as a function of time. This allows to discriminate an early stage of
conversion, followed by an extended coarsening stage. The small angle
scattering (SALS) appears only long after completed conversion and exhibits
Furukawa scaling for all times. Additional microscopic experiments reveal that
the grain boundaries have a reduced Bragg scattering power but possess an
increased refractive index. Fits of the Furukawa function indicate that the
dimensionality of the scatterers decreases from 2.25 at short times to 1.65 at
late times and the characteristic length scale is slightly larger than the
average crystallite size. Together this suggests the SALS signal is due
scattering from a foam like grain boundary network as a whole.
