  We predicted and observed for the first time the quasi-specular albedo of
cold neutrons at small incidence angles from a powder of nanoparticles. This
albedo (reflection) is due to multiple neutron small-angle scattering. The
reflection angle as well as the half-width of angular distribution of reflected
neutrons is approximately equal to the incidence angle. The measured reflection
probability was equal to ~30% within the detector angular size that corresponds
to 40-50% total calculated probability of quasi-specular reflection.
