Ternary Representations of Ancient Chinese Bronze Compositions

The simple method of representing the percentages of copper, tin, and lead in an alloy on a three-component plot has helped to categorize ancient Chinese bronze compositions. While the representation method is straightforward and the plots can be drawn by computer, some of the problems involved, such as the methods of grouping values on the plot and the normalization procedure, are not trivial. The ternary representations give new insights into the evolution of bronze alloys in China, show clearly the great control over alloy composition exerted by ancient Chinese foundrymen, and reveal the casters remarkable grasp of the metallurgy of the copper-tin-lead system. Ternary representations have helped to assess the date at which an object could have been made and to show, graphically and imemdiately, any inconsistencies between stylistic and technical attribution to period.