The origin of blue and white?

Blue-and-white porcelain, also known as white porcelain, is made of cobalt ore containing cobalt oxide as raw material, with decorative patterns painted on the ceramic blank and covered with a layer of transparent glaze, which is once fired by high temperature reducing flame. An underglaze color. Cobalt is blue after firing, which has the characteristics of strong coloring, bright hair color, high firing rate and stable color. At present, the earliest blue-and-white porcelain specimens are found in the Tang Dynasty (some scholars say that blue-and-white porcelain in the Tang Dynasty is not blue-and-white porcelain); Mature blue and white porcelain appeared in the Yuan Dynasty; Blue and white became the mainstream of porcelain in Ming dynasty; It reached its peak in the Kangxi period of the Qing Dynasty. During the Ming and Qing Dynasties, colorful blue and white, peacock green glazed blue and white, bean green glazed blue and white yellow and old glazed blue and white were also created and fired. It was in the Tang Dynasty, the most famous in the Ming and Qing Dynasties.