They have also been used to improve the efficiency, eco-friendliness, and economic aspects of existing materials to make them ultimately more marketable. Let me emphasize also that the practical importance of these metals goes well beyond wind turbines, hybrid and electric vehicles, energy-storage technologies, compact fluorescent lights, and these kinds of things, which are collectively known as green or environmental technologies.
Je dois souligner que l'importance pratique de ces métaux est loin de se limiter aux éoliennes, aux véhicules électriques et hybrides, aux technologies de stockage de l'énergie, aux lampes fluorescentes compactes et autres technologies dites vertes.