1, medical stone is not a coating, medical stone is a natural silicate mineral, and it is non-toxic. Medical stone is a kind of compound mineral or medicinal stone which is non-toxic and harmless to organisms and has certain biological activity. The main chemical composition of medical stone is inorganic aluminosilicate.

2. Medical stone belongs to volcanic rocks, and the main mineral is volcanic rocks. Lava erupted from volcano is buried underground, which is transformed into acidic substances under the action of high humidity and high heat in volcanic zone, and finally medical stone is formed under the pressure of crustal change. It can be inferred that medical stone is produced in volcanic zone.