This is a rather larger netted veinal polymetal ore deposit of composite greisen-skarn type rich in tungsten-tin-bismuth-molybdenum (beryllium) and lead-zinc etc. Garnets are the principal mineral in skarn, about 60-75% , of andradite and grossularite group. They are most closely related to W, Sn, Bi, Mo(Be) etc mineralization. Bused on our researches on 50 garnets of I, II, III different generations the results are given as follows; 1 .Garnet has abnormal optical properies, that are of three kinds: the optic isotrope, weak optic anisotrope and powerful optic anisotrope. 2 .Garnets of the early period occur in the lower part of, skarn, they are dark colour and optic isotrope, N=1.852-1.781, D=3.802-3.550, a0= 11.9692-11.9491, belonging to andradite groups. Towards the upper part of skarn they gradually become light colour’and powerful optic anisotrope, N= 1.752-1.790, D=3.618-3.657,ao=11.8579-11.8684,belonging to grossularite. 3 .Garnet groups are the complete isomorphism interuiediate composition between and radite-grossularite. 4 . Garnet has a higher content of tungsten-tin W = 0.2-1.0% and Sn= 0.3-0.4%，W exists in the form 'of scheelite and wolframits, but Sn sudstitu- tes for Fe and exists with little content in the form ofcassiterite and stannite in garnet. 5 .Andradite is formed under conditions of high temperature (T>400℃)， pH=6.64-6.98 and Eh“3-14, mainly in the way of dimetasomatism, while grossularite is formed under the conditions of low temperature (T=300-400℃)， pH=6.24-6.78 and Eh=一3一+4, and mainly in the way of contact-infiltra- tion metasomatism.