  It is observed experimentally that the coercive field has an anomalous
angular dependence at temperatures above the blocking temperature in physically
nonpercolated granular films CoFeB-SiO$_{2}$ with anisotropic granules oriented
in the same direction. It is shown that the anomaly is determined by the
singularity of an angular dependence of the critical field causing the absolute
loss of phase stability of the superferromagnetic state of an ensemble of
interacting superparamagnetic granules.
