We present an experiment of densification of a 2D horizontal assembly
made of regular pentagons. The annealing leads to a dense crystalline
arrangement with quasisixfold symmetry in spite of the geometrical cha
racteristics of the grains and of the a priori short-range correlation
length in the packing. This configuration yields the maximum average
number of side to side contacts between the grains and probably the ma
ximum packing fraction.