Abstract:There occurs,in S. E. China, a broad region of granite masses the acidity of whichincreases with ages from prelower Palaezoic to late of Cretaceus.The associ- ated mineral deposits are, W, Sn, Mo, Bi f Cu, Pb, Zn; Li, Be,B y Nb, Ta and rare earths, forming the socalled the Chinese part of the Circum-Pacific polymetallic Zone. The ore bodies appear as vein, greisen or skarn, usually on the tops of cupolas. The granite and the oreTbodies were cut by fine grained porphyritic granite dykes, which were, in turn, cut by basic or ultrabasic dykes. By investigating 200, samples of granites, greisens and skarns of different ages and localities, it appears that micas vary significantly with barren, slight- 1y altered granite and greien-skarn associated with orebodies. Micas play a role of absorber or reservoir of rare or oreforming elements which either enter, as building stones, into the micastructure or as independent minerals enclosed in or enriched around micas. The physical, including colors, and chemical proper- ties of micas depend on the kinds of parent rocks and associated minerals. The micas are, 1 .Normal biotite and muscovite in barren or unaltered granites, 2. Slightly altered micas and 3. Much altered micas associated with ore deposits a) Rubidian zinnwaldite in altered granite and greisen with niobites grey green; 2-3mm; with pinacoidal or prismatic facess containing Li20 3.28,Rb2O 1.54, F 7.16%;and with diffused streaks much developed in Laue photograph. b) Zincian siderophyllite in niobite granite;containing Li2O 0.94,MnO0.91, Na20 1.5, ZnO 0.46 and F 4.6%. c) Be-margarite in the central parts of mica veinlets in stockwork marbles with maximum Be0 1.33%.