- Very finely divided cerium oxide is used for optical polishing; it's usually mixed with a vehicle such as glycerine or mineral oil to form a paste.
- Also 99% of all white LEDs use Ce-doped Y3Al5O12 (YAG:Ce) as a yellow emitter. The material absorbs blue light from the LED and converts it to yellow. Blue + Yellow = cold white. Add a red emitter like Sr2Si5N8:Eu2+ and you get warm white.
- Woo... magnets! ^_^
- Why didnt they mention lighter flints? Thats probably the most common use of cerium