PHASE-EQUILIBRIA FOR THE FE2SIO4-FE3O4 SYSTEM UNDER HIGH-PRESSURE

High pressure phase relation of the system Fe2SiO4-Fe3O4 was investiga ted by synthesis experiments using multi-anvil high pressure apparatus , A complete solid solution with spinel structure along Fe2SiO4-Fe3O4, join occurs above 9 GPa at 1200 degrees C. Lattice constants of the s olid solution show almost linear variation with composition. A spinell oid phase is stable for intermediate compositions in the pressure rang e from 3 to 9 GPa. the synthesized spinelloid phase is successfully in dexed assuming nickel aluminosilicate V type structure.