  The production of Primordial Black Holes (PBH) from inflationary
perturbations provides a physical process where the effective classicality of
the fluctuations does not hold for certain scales. For adiabatic perturbations
produced during inflation, this range of scales corresponds to PBH with masses
$M\ll 10^{15}$ g. For PBH with masses $M\sim M_H(t_e)$, the horizon mass at the
end of inflation, the generation process during the preheating stage could be
classical as well, in contrast to the formation of PBH on these scales by
adiabatic inflationary perturbations. For the non evaporated PBH, the
generation process is essentially classical.
