White porcelain is actually made of clay, but it has a glaze coating on its surface. After being heated at high temperature, it will release substances harmful to health. The purple casserole does not contain any chemical coating, and is rich in a variety of mineral trace elements, which is very fragrant whether cooking soup or cooking.

However, because high-quality purple sand is more expensive, some black-hearted manufacturers will use the soil dyed with dyes as the raw material of the inner container, so the quality of the purple casserole is not easy to grasp. If you buy inferior purple casserole, the damage can not be underestimated.