<unk>  is a luminescence that is mostly found as an optical phenomenon in cold bodies, in which the molecular absorption of a photon triggers the emission of another photon with a longer wavelength. The energy difference between the absorbed and emitted photons ends up as molecular vibrations or heat. Usually the absorbed photon is in the ultraviolet range, and the emitted light is in the visible range, but this depends on the absorbance curve and Stokes shift of the particular<unk> uorophore.<unk>  is named after the mineral<unk> uorite, composed of calcium<unk> uoride, which often exhibits this phenomenon.
Fluorescence
Swelling 
Fluency
Stripping
Density
Chemiluminescence
Luminous intensity
Aqueous humour