Magnets (Neodymium, Praseodymium, Terbium, Dysprosium, Samarium): Motors, disc drives, MRI, power generation, microphones and speakers, magnetic refrigeration Metallurgical alloys (Lanthanum, Cerium, Praseodymium, Neodymium, Yttrium): NimH batteries, fuel cells, steel, lighter flints, super alloys, aluminum/magnesium Phosphors (Europium, Yttrium, Terbium, Neodymium, Erbium, Gadolinium, Cerium, Praseodymium): display phosphors CRT, LPD, LCD; fluorescent lighting, medical imaging, lasers, fiber optics Glass and Polishing (Cerium, Lanthanum, Praseodymium, Neodymium, Gadolinium, Erbium, Holmium, Baryte): polishing compounds, decolorizers, UV resistant glass, X-ray imaging Catalysts (Lanthanum, Cerium, Praseodymium, Neodymium, ruthenium, rhodium, palladium, osmium, iridium, platinum): petroleum refining, catalytic converter, diesel additives, chemical processing, industrial pollution scrubbing Other applications: Aerospace: Beryllium Aluminum production (fluorspar), alloys (Magnesium, Scandium) Catalytic converters (Cerium) Cathode-ray tubes (Gadolinium, Terbium, Yttrium) Ceramics (Fluorspar) Computer chips (Indium) Defense (Neodymium, Praseodymium, Dysprosium, Terbium, Europium, Yttrium, Lanthanum, Lutetium, Scandium, Samarium) Drilling oil and gas (Baryte) Electric vehicles (Niobium) electric motors (Samarium) Electronics and electricity (Tungsten) Fertilizers Fire retardants (Antimony) Fiber optics (Germanium, Erbium) Fuel cells (SOFC use lanthaneum, cerium, prasedymium) Healthcare (Baryte, Erbium) Hybrid engines (Dysprosium) Integrated circuits (silicon metal) Lasers (Europium, Holmium, Ytterbium) LCD screens (Indium) Lenses (Lanthanum) Light-emitting diodes (LEDs) (Gallium) Lighting (Lanthanum, Samarium, Europium, Scandium) Luminescent compounds (Promethium) Mettalurgy and alloys (Baryte, Cerium) Nuclear power (Europium, Gadolinium, Cerium, Yttrium, Sm, Erbium, Beryllium, Niobiumm /sanaruyn) Oil refinery (Cerium) Optics (fluorspar) Phones, computers, hybrid vehicles, magnets (Cobalt) Photovoltaic cells (Germanium, silicon metal) Pigments Satellites (Niobium) Semi-conductors (gallium, Holmium) Steel production (coking coal, fluorspar, vanadium, Ytterbium) Superconductors (high-temperature) Bismuth, Thulium, Yttrium Superconductive compounds (Lanthanum) Telecommunications and electronics (Beryllium) Thermoelectric auto generators (Bismuth) Water Treatment. using above data build app with above said elements images taken from internet websites with explaination of usage all in fields of sciences .