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Cu and Fe skarns are the world's most abundant and largest skarn type deposits, especially in China, and Au-rich skarn deposits have received much attention in the past two decades and yet there are few papers focused on schematic mineral deposit models of Cu-Fe-Au skarn systems. Three types of Au-rich deposits are recognized in the Edongnan region, Middle-Lower Yangtze River metallogenic belt:~140 Ma Cu-Au and Au-Cu skarn deposits and distal Au-Tl deposits; 137-148 Ma Cu-Fe; and 130-133 Ma Fe skarn deposits. The Cu-Fe skarn deposits have a greater contribution of mantle components than the Fe skarn deposits, and the hydrothermal fluids responsible for formation of the Fe skarn deposits involved a greater contribution from evaporitic sedimentary rocks compared to Cu-Fe skarn deposits. The carbonate-hosted Au-Tl deposits in the Edongnan region are interpreted as distal products of Cu-Au skarn mineralization. A new schematic mineral deposit model of the Cu-Fe-Au skarn system is proposed to illustrate the relationship between the Cu-Fe-Au skarn mineralization, the evaporitic sedimentary rocks, and distal Au-Tl deposits. This model has important implications for the exploration for carbonate-hosted Au-Tl deposits in the more distal parts of Cu-Au skarn systems, and Fe skarn deposits with the occurrence of gypsum-bearing host sedimentary rocks in the MLYRB, and possibly elsewhere.