Major element analysis of the Duckyong quartzite using X-ray fluorescence for evaluating its potential as a reference material

Abstract

In this study, the concentrations of major to trace elements in Duckyong quartzite, South Korea, were measured using wavelength-dispersive X-ray fluorescence to evaluate its potential as a reference material for silica stones and silica sands. To assess the homogeneity of the Duckyong quartzite (DK), the inter-laboratory comparisons and repeated analyses (n = 160) were conducted on powdered samples. Additionally, the newly produced glass disk samples of Duckyong quartzite (KSi-2), previously produced in 2002, were reanalyzed to monitor possible change in composition over time. The measured values of DK samples were consistent with those of KSi-2 samples within uncertainties. The analytical results of re-evaluated KSi-2, which had been stored for an extended period, were consistent with previously reported values within uncertainties, reflecting the high stability of Duckyong quartzite samples. The measured nine major elements and loss on ignition (LOI) of the Duckyong quartzite samples (DK + KSi-2) in new and previously studies were as follows: SiO2, 98.39 ± 0.15 wt.%; Al2O3, 0.70 ± 0.01 wt.%; Fe2O3, 0.24 ± 0.01 wt.%; CaO, 0.014 ± 0.005 wt.%; MgO, 0.03 ± 0.01 wt.%; K2O, 0.16 ± 0.01 wt.%; Na2O, 0.02 ± 0.01 wt.%; TiO2, 0.039 ± 0.001 wt.%; P2O5, 0.011 ± 0.002 wt.%; and LOI, 0.34 ± 0.09 wt.%. The uncertainties of the measured values were within ± 0.2 %, indicating the homogeneity of Duckyong quartzite. This geochemical study indicates that the Duckyong quartzite, with high homogeneity and stability, is suitable as a natural geological reference material. It is anticipated to be utilized extensively in the testing field for silica-stone and silica-sand analyses. © 2024, Korea Society of Analytical Science. All rights reserved.