Selectively Gd-Enriched Micro- and Nano-Sized Minerals in the Lunar Regolith from the Crisium Mare

摘要

The direct SEM examination of the finest fraction, which was dispersed onto the adhesive carbon tape, is an efficient method for mineralogical study of lunar regolith. No carbon or metal was used for sample sputtering, since the carbon tape area between particles was large enough to neutralize the charge. Using such a preparation technique, the sample was poured out onto the adhesive surface immediately after ampule recovery under sterile conditions. Then, the obtained specimen was pressurized for electron microscopic investigation. The absence of intermediate operations minimized the possible pollution of the specimen by extraneous phases. This is very important for investigation of the lunar regolith, especially nanoparticles. Such a technique made it possible to discover several unique mineral phases in the regolith obtained by Soviet automatic stations (AS) Luna 16, Luna 20, and Luna 24.