Searching for a magnetic proximity effect in magnetite-carbon structures
  In order to study a possible magnetic proximity effect in magnetite-carbon structures, we have performed magnetization measurements of graphite-magnetite composites with different mass ratios as well as the measurement of the magnetoresistance of one of them and of the magnetization of a magnetite-carbon bilayer. The overall results do not indicate the induction of bulk ferromagnetism in graphite and disordered carbon structures through their contact with magnetite. 
R. H\"ohne, M. Ziese and P. Esquinazi