The conditions of the formation of different magnetic structures with ferro
magnetic (FM) and antiferromagnetic (AFM) ordering in granular materials co
ntaining a subsystem of ferromagnetic granules are considered within the ph
enomenological approach. It is supposed that the magnetostatic field and th
e exchange interaction between conduction electrons and magnetic ions are r
esponsible for the formation of magnetic structure. (C) 2000 MAIK "Nauka/In
terperiodica".