The twelve measures and the six assistant methods (RNM) put forward by Mr.Ren Nan provide us one system of unique know-how to distinguish Ancient Hongshan Jade.

• 任南先生提出的鉴别红山古玉的12字诀和6种辅助方法，即任氏鉴定法（RNM）为我们提供了独有的技术诀窍。