Celestine also known as celestite is relatively soft so must be handled carefully. Although best known for its blue crystals, they also occur in several other colours including white. They can also be colourless.
The names celestine and celestite come from the Latin 'caelestis' meaning 'of (or) in the heavens' which metaphorically can also mean 'divine' or 'god-like'. Both stem from the mineral's heavenly blue colour.
Interestingly celestine is the main source of the chemical element strontium. This is widely used in fireworks and alloys. Strontium is a soft silvery white yellowish metal.