The invention relates to pearlescent pigments with a platelet-shaped
substrate comprising metal oxide and having a first and a second
protective layer, said metal oxide having a refractive index of greater
than 1.8, there being on the platelet-shaped substrate a first protective
layer comprising cerium oxide and/or cerium hydroxide and a second
protective layer of SiO.sub.2, applied to which is an organic chemical
aftercoat comprising at least one silane having at least one functional
bond group and at least one silane without a functional bond group, it
being possible for metal oxide layers other than cerium oxide and
SiO.sub.2 to be disposed between the first and the second protective
layer. The invention further relates to a process for preparing these
pigments, and to the use thereof.