Non-Destructive Identification And Quantification Of Ilmenite From A Single Particle Of The Chang’E-5 Lunar Soil Sample

Abstract

: Ilmenite (FeTiO 3 ) is an early crystallization product of lunar magma and is the most abundant oxide mineral in lunar mare basalts. It is an important lunar resource that is mainly used for He and O 2 production, but also as a source of Fe. Therefore, the identification and quantification of ilmenite from lunar mare basalts is crucial to better understand lunar geological processes and develop lunar resources. Herein, a correlative micro-X-ray fluorescence (µXRF) and three-dimensional X-ray microscopy (3D XRM) approach was applied to non-destructively identify and quantify ilmenite from micro-sized single particles in China’s Chang’E-5 (CE-5) lunar soil samples. Ti-rich particles (P15 and P17) were selected from CE-5 lunar soil samples using scanning µXRF measurements. Scanning electron microscopy (SEM) indicated that both particles contained tiny ilmenite grains, but different major minerals. Ilmenite grains within these two particles were visualized and quantified using 3D XRM analyses. The ilmenite mass fractions estimated using the 3D XRM technique were similar to those obtained via µXRF quantification. Therefore, this study provides a novel nondestructive strategy for rapid ilmenite identification and quantification from single particles in CE-5 soil samples. This protocol can be replicated to characterize ilmenite and other minerals in precious extraterrestrial samples.