Technology and Identification of Tianhuang Imitation with Dickite as Its Main Mineral Component

Since its high price, Tianhuang has many imitation products on the market. Among those imitations, it is the most difficult to identify the Tianhuang imitation whose main mineral component is dickite. In order to find out the key identification basis of dickite-type Tianhuang imitation, the infrared spectroscopy, Raman spectroscopy, X-ray fluorescence spectroscopy, ultraviolet spectroscopy were conducted on the dickite-type Tianhuang and its imitation samples, which are routinely tested and purchased from the market. Through data analysis and comparison of UV-Vis spectrum and scanning electron microscope micro-topography analysis, etc., it was found that dickite-type Tianhuang imitation can be divided into: Pb-containing material for surface imitation to imitate "silver-wrapped golden" Tianhuang; Pb material for surface initation superimposed dyeing treatment to imitate "Huangpi" Tianhuang; Ag material processed "crowskin" Tianhuang imitation, etc. The results showed that in the daily identification, infrared spectroscopy cannot be used as the basis for the identification of dickite-type Tianhuang and its imitation. Magnified observation, component analysis and UV-Vis spectrum analysis can be used as the key basis. The results of Raman spectroscopy can be used as a reference for the identification of Tianhuang imitations with dickite as its main mineral component.