The
Zhilingtou Au-Ag deposit is situated in the eastern part of the complexly
deformed and metamorphosed South China Caledonian Fold Belt. It consists of
seven orebodies that are almost exclusively hosted by biotite plagioclase gneiss of
the Precambrian Chencai Group. They form an apparent en echelon pattern
in both cross-section and level plan. Three different ore types, based
on mineralization textures, have been recognised within the Zhilingtou lode.
These are Au-Ag-rich quartz veins, Au and Ag-bearing silicified rocks and Au-Ag-containing
altered rocks with quartz stockworks. The mineralisation is principally composed
of electrum, argentite, pyrite and minor sphalerite, galena as well
as traces of hessite and chalcopyrite plus a gangue assemblage of quartz, rhodonite,
sericite and chlorite. Fluid inclusions related to Au-Ag mineralisation yield
a wide range of homogenisation temperatures from 110 to 447C, with
two distinctive peak values at 250 - 300C and 350 - 400C
respectively. 30Si values of quartz veins and silicification from
the three stages of mineralisation range from -0.1 to -0.4. The mineralisation at Zhilingtou is interpreted
as forming by recirculated meteoric water extracting ore-forming elements from
metamorphic rocks due to Mesozoic volcano-magmatic activity.