Porcelain boxes, such as these fine examples, would have been not only used as everyday containers, but also placed as grave goods with the deceased. Blue and white porcelain is one of the most emblematic productions of Chinese art, reaching its apex with the Kangxi period of the Qing Dynasty. Blue and white porcelain was created by painting designs with the distinctive cobalt-oxide mixture under the glaze. Cobalt ores were imported from Persia, and were considered precious ingredients at the time, used only in limited quantities. Cobalt ores were ground into a pigment, which were painted directly onto the smooth porcelain body. The piece was then glazed and fired. When fired in the kiln, the cobalt would have reacted to generate the distinctive bright sapphire blue colour. In Chinese culture the blue colour always held a special and deep meaning. Often linked with the season of spring, blue is associated with growth and advancement.