commonly known as Burnt Lime, Caustic Lime, Lime, or Quicklime is a widely
used chemical compound. It is a white caustic alkaline crystalline solid
used in Glass production. Its ability to react with Silicates makes it
useful in modern metal production. It is also used in water and sewage
treatment to reduce acidity. Calcium Oxide luminesces at high temperatures
producing a brilliant white light ( 'limelight' ).
( Material Safety Data Sheet )