  Magnetization measurements prove that the magnetic properties of large-angle
(theta > 30o) bismuth bicrystals with crystallite interface (CI) of twisting
type essentially differ from well-known results on single-crystalline
specimens. Two superconducting phases were observed at CI of bicrystals
(ordinary rhombohedral Bi is not a superconductor). It was shown that one of
them (phase with Tc ~ 8,4 K) is localized in central part of crystallite
interface. It was also found that in adjacent layers (width of layer d2 ~ 20
nm) of CI the proximity effect is significant.
