Abstract
We study about serpetinites from Mineoka belt, Boso Peninsula, Chiba Prefecture. Serpentinites mainly onsist of mesh texture and bastite. Ni sulfides are often observed and a few awaruite and native copper are also observed. Values of (Ni+Fe)/S about Ni sulfides changes from 0.78 to 1.82. Perfectly serpentinized mesh texture consist of Fe-rich serpentine or magnetite.