Determination of multi-element concentrations at ultra-low levels in alternating magnetite and pyrite by HR-ICP-MS using matrix removal and preconcentration

• Aimed at the 28 trace element analysis in alternating magnetite and pyrite
• Anion-resin and TRUspec ion-resin were used to separate the Fe matrix.
• Multi-step methods of TRUspec resin effectively remedy the limited Fe exchange capacity.
• High quality data of samples revealed a genetic relationship between two deposits.

This work presents a solid phase extraction (SPE) method for pre-concentration of 28 elements at ultra-level in magnetite and pyrite samples prior to their analysis using ICP-MS. The TRUspec resin and AG1-X8 anion resin were employed for the precise and accurate determination of Cr, Co, Ni, Cu, Zn, Ge, Rb, Sr, Ba, Cs and Li, Be, Sc, Cs, REEs, respectively. The recoveries for all the analytes were 100% ± 5% with low procedural blanks. The method was validated by Iron Formation reference material (FER-2), showing good agreement with literature value. The proposed method was employed for the analysis of magnetite and pyrite samples from alternating magnetite-rich and pyrite-rich mesobands. The obtained high quality data can be used to establish the genetic relationship between these two types of deposits.