AbstractEnergy‐dispersive x‐ray fluorescence was used to study the variations in the elemental concentrations of ceramic glazes. The results show the constancy of the concentrations of Rb, Sr, Y, Zr and Nb and also of the Mn/Co ratio determined at different positions in a piece of porcelain. They also show that during the Qing dynasty, it was common practice to use a different glaze for the base of a piece of porcelain, in contrast to the modern practice of using the same glaze for the whole pi