Determination of 15 Rare Earth Elements in Hetian Jade by Inductively Coupled Plasma-Mass Spectrometry with High-pressure Closed Digestion

Abstract

BACKGROUND There are abundant rare earth elements in Hetian jade. The accurate determination of the content of rare earth elements is of great significance for revealing the source of ore-forming materials, the nature of ore-forming fluids and the genesis of the deposit. OBJECTIVES To compare the different acid systems in microware digestion and investigate the elimination test of polyatomic interferences, so as to develop a method for the determination of REE in Hetian jade by inductively coupled plasma-mass spectrometry (ICP-MS) with microwave digestion. METHODS After comparing the efficiency of HNO3-HF acid dissolution and Li2B4O7-LiBO2 fusion, the Hetian jade samples were digested by HNO3-HF. Fifteen rare earth elements were determined by ICP-MS. 103Rh and 49In are used as internal isotopes to complement matrix effect and correct sensitivity drift, in order to reduce matrix effect. RESULTS The detection limits of the method were 0.0008-0.0091μg/L, whereas the recoveries were 101.0%-120.0%. The relative standard deviation was 0.55%-1.83%(n=11). CONCLUSIONS This method uses less acid and has a low blank value. It is applied to the analysis of Hetian jade in different regions. The distribution pattern of rare earth elements is characterized by right-inclined light rare earth enrichment, which provides constraints on the genesis of the jade deposit.

Keywords

• hetian jade
• trace elements
• rare earth elements
• inductively coupled plasma-mass spectrometry