Traditional Chinese medicine can't be boiled in a glass jar, because there are acidic substances in traditional Chinese medicine, which will chemically change with the glass jar, thus releasing harmful substances. So Chinese medicine can't be cooked in a glass pot, but only in a casserole and ceramic pot.

Moreover, iron pots, copper pots and aluminum pot can't be used when decocting medicine, mainly because these pots contain iron ions, copper ions and aluminum ions. Their chemical properties are unstable and easy to be oxidized. It is easy to react with the chemical components contained in traditional Chinese medicine when decocting, and even cause poisoning in serious cases.