Quartz Crystallinity Index of Arabian Sands and Sandstones

Abstract

Quartz, a dominant resistant component in many rocks and sediments, crystallizes under varying thermodynamic and kinetic conditions (Götze, 2012). Quartz crystallinity index (QCI) is a semi-quantitative 0-10 scale that expresses the crystallinity of powdered quartz by measuring the intensity of the (212) X-ray diffraction peak (Murata & Norman, 1976). Although not thus far attributed to any particular crystal-structural property (Broekmans, 2012;Marinoni & Broekmans, 2013), QCI has successfully distinguished between quartz forming under different crystallization conditions including temperature, pressure, rate of crystallization, and age (Katayama et al., 1989;Murata & Norman, 1976). In addition to sedimentary provenance studies, QCI has been considered for use in civil engineering (to predict deleterious reactions in concrete) and in medicine (to predict the toxicity of quartz dust of respirable size) (Altree- Williams & Clapp, 2002;Katayama et al., 1989).Individual provenance tools can be misleading, and multiple tools should always be integrated for conclusive provenance determinations (Garzanti, 2016;Garzanti et al., 2013). Several studies have focused on using QCI in tracing east Asian dust provenance. They traced the dust from their source areas including river sediments, dry lake sediments, and mountain loess (Isozaki et al., 2020;Sun et al., 2013) to their sink including desert sediments (Sun et al., 2007), hemipelagic sediments (Nagashima et al., 2007), paleosols (Sun et al., 2008), and dust (Yan et al., 2015). QCI, in combination with electron spin resonance (ESR) signal intensity, has effectively:1. Discriminated among nine major deserts in east Asia and provided signatures for them as source tracers to distinguish dust provenance in marine and terrestrial environments (Sun et al., 2007(Sun et al., , 2013) 2. Recognized a distinct quartz origin for different size fractions of hemipelagic sediments from the Japan Sea (Nagashima et al., 2007) and desert sediments (Sun et al., 2007)

Assessment of Crystallinity Degree of Quartz Raw Materials

“…Рассчитанные нами значения индекса кристалличности кварцитов и природного кварца удовлетворительно согласуются с оценками кристаллических, например, кварцевых песков [44].…”

Insight into Crystalline Structure and Physicochemical Properties of Quartz-Carbon Ore

“…The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/min13121488/s1, Figure S1 S1: chemical composition of pristine QZC by XRF and TOC; References [38][39][40][41][42].…”