摘要
A large independent cadmium deposit has been found at Niujiaotang, Duyun, in recent years. To the bestof our knowledge this represents the first case of its kind in the world. With a reserve of over 5 000 tonsof cadmium, the deposit is unique in its high concentrations of cadmium which are tens of to over onehundred times higher than in ordinary cadmium mineralizations associated with Pb-Zn deposits. 1 Geological characteristics The Niujiaotang deposit is located at the southwest margin of the Yangtze Plate. The region consistsof a thick sedimentary cover ranging from Sinian to Triassic in age overlying unconformably the basementof Mid-Proterozoic metamorphosed volcanic-sedimentary rocks. Lower Cambrian carbonate strata arcoutcropped in the mining district. Cadmium mineralizations, with seven layers recognizable, are devel-
