Jiuyang purple casserole is the same as purple casserole. Jiuyang casserole is made of purple sand, so it is also called Jiuyang purple sand casserole. Identify the authenticity of Jiuyang teapot, look at the color: the color of pure purple sand, whether it is purple, yellow, red or the color between them, must have a jade-like charm. Its light quality is dark, just like oiling, the more polished it is, the less waxed it can be. You can refer to the material effect of old jade. The rarer the material, the more valuable it is.