of Tsukuba, Tsukuba-shi, Tennoudai, Ibaraki 305, Japan bMaster's Program in Sciences and Engineering, Universityof...Universityof Tsukuba, Tsukuba-shi, Tennoudai, Ibaraki 305, Japan cChemical Analysis Center, Universityof Tsukuba...Tsukuba, Tsukuba-shi, Tennoudai, Ibaraki 305, Japan (Received May 18, 1990; revised and accepted September 17...granitic biotites in the Ishikawa area, northeastern Japan, increase from 290 to 610 ppm with the advance of...skarn deposits and their adjoining granitoids in Japan (Fig. 1 ). Of these samples, bulk analyses by means |