This bottle vase is decorated with a flambé glaze, a mixture of deep copper red and turquoise blue. The technique, known in China for centuries, was emulated in the nineteenth century by French art potters led by Chaplet. It involved the oxidation of copper in the kiln (reduced oxygen to create red; increased oxygen for blue). One critic wrote, "M. Chaplet, who, after thirty years of special study, also seems to have gained absolute control over his capricious materials, so that, apparently at will, he can, on a single piece, obtain the most unexpected and diverse effects of color."