Authentic medicinal materials (daodi yaocai 
) is also known as pure, typical medicinal materials (didao yaocai 
), a special term used for pure, high-quality medicinal materials. It refers to those medicinal materials with unique regional characteristics, having a long history, suitable place of production, good variety, exquisite preparation process and prominent curative effects. Generally, the authenticity of medicinal materials is determined based on their place of production, variety, quality, etc.
Authentic medicinal materials which result from long-term medicine usage and practice are not invariable. Environmental changes will cause the medicinal plants to become extinct, e.g. after the extinction ofshangdang ginseng 
, ginseng from the northeastern region became a favourite herb among the people. As notoginseng (sanqi 
) was produced in Guangxi, it was named asguangsanqi 
, and later known as diansanqi 
(dian 
is another name for Yunnan) when it gained popularity in Yunnan where it became notoginseng’s new region of production.
Moreover, the limited production of various authentic medicinal materials is unable to meet demand. People therefore introduce and cultivate new varieties, e.g. importing aucklandia root 
, cloves 
, American ginseng 
, nutmeg 
, etc. from abroad. After extensive research, these produce varieties of a quality almost similar to that of the authentic medicinal materials. Thus, some of the demand for those medicinal materials in shortage can be satisfied.
Distribution of Chinese medicinal materials
