For the blue pigment painted on the Northern-sung blue-and-white ware excava-ted in Chekiang province, the MnO/CoO and Fe_2O_3/CoO ratios are 10.25 and 0.61 respecti-vely, these values quite near those of the native cobalt ores.

• 画在北宋浙江省发掘的青花瓷器上的青花色料的MnO/CoO比和Fe_2O_3/CoO比分别为10.；25和0