Chinese medicine keel, why does it have tongue-absorbing power, but fake keel (other bones) does not? Is this method absolutely accurate in judging the authenticity of keel?

Because the real keel is made of the bones of ancient mammals, such as elephants, rhinoceroses, three-toed horses, etc., under the long-term geological and environmental factors, the bones have changed, and the permeability of the bone surface is greater, so the hygroscopicity is stronger. So the tongue is attached to the bone surface, and the bone surface has the ability to absorb the tongue. False keels should be treated differently. It is made of animal bones. Because it has not been affected by long-term geological factors, it has poor air permeability and lower tongue absorption. There is also a kind of kaolin that is widely used, because it is connected into pieces in the ore, and because of minerals, it has spots on it, much like a keel, but it is not actually an animal bone, so it has no tongue-absorbing force. Therefore, it is not that the authenticity of the keel can be absolutely and accurately judged by the tongue absorption force, but this method is simpler and more effective. If some suspicious drugs need chemical identification, it is the most accurate and effective.