Magnetic Moment Peculiarities in Bismuth Bicrystals with Large   Crystallite Disorientation Angles
  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. 
F.M.Muntyanu, A.Gilewski, K.Nenkov, J.Warchulska, A.J.Zaleski