Underlying the most subtle chemical and optical properties of these elements and their compounds in the condensed state are the crystal field effects. This phenomenon in non-metallic compounds is discussed in chapter six. The volume opens with a review of important new solvent extraction procedures as well as emerging alternative separation processes such as photochemical separation, precipitation stripping and supercritical extraction. Scientific and industrial procedures are illustrated. In a further chapter eight major analytical techniques of obtaining accurate trace analysis are examined, tabulated and assessed. The most effective procedures of each are also reviewed. Chapter two considers a wide variety of methods using rare-earth solutions and slats to modify advantageously the costly deterioration of metals and alloys. This topic is expanded in the following chapter, paying particular attention to protection against high-temperature oxidation, sulfidization and hot-salt corrosion. The following two chapters are concerned with the versatility of the rare earths in addressing current technical problems such the use of rare-earth intermetallics, principally LaNi3-based materials, to provide the skyrocketing need for environmetally friendly, usually portable, battery power. The final chapter is a review of the solvation, interaction and coordination of rare-earth salts in a variety of organic solvents including dimethylacetamide, dimethylsulfoxide, various alcohols, acetonitrile and propylenecarbonate under strict anhydrous conditions. A contrast of these interactions with those in which water is present with organic solvents is also made.