Abstract: Lantian jade was once praised as one of the famous great Chinese jades. Modern Lantian jade specifically refers to the serpentinized marble in Lantian, Shaanxi Province, which occurs in Yuchuan and Hongxing areas of the Middle Proterozoic Kuanping Group. But what is exactly "Lantian jade" in history? There still has been much controversy. By means of combing and analyzing the archaeological discovery and historical documents of Shaanxi Lantian and the surrounding areas, as well as testing the gemmological characteristics of modern Lantian jade, this study aims to explore the material features, cultural connotation, the use of history and developing process of ancient and modern "Lantian jade", and provide a reference for the market development and connotation exploration of Lantian jade. The main conclusions are summarized as follows: (1) According to the test results of the Neolithic jades unearthed from Xinjie Archaeological Site in Lantian, the early "Lantian jade" was serpentine, which could be one of the prehistoric "Xuan Yu"; (2) Based on the textual research in documentation, the ancient "Lantian jade" after the Qin-Han Dynasties with delicate texture and moist luster, was probably tremolite; (3) Combined with previous work, this study shows that modern Lantian jade should include at least two types of jades: serpentine marble jade with granular structure and serpentine jade with fibrous structure; (4) The above results indicate that the material of "Lantian jade" has experienced major changes from serpentine jade to tremolite jade to serpentinized marble during the different historical periods, when the connotation of "Lantian jade" has been varied obviously. Therefore, if Lantian jade is simply named as serpentinized marble on the basis of the present regional output, the realization of "Lantian jade" cultural connotation value will be restricted seriously.