There is no such thing as CFL glass. CFL stands for compact fluorescent light. CFL refers to what makes the light. This is caused by the fluorine in the tube, when excited by high voltage it glows, making light. This light is of a certain color temperature or Kelvin. The color of the light is what causes one to see something change. The white light made of all colors has more of some than others or is missing some colors, and this is what makes the glass change. The glass has minerals that reflect or absorb certain color wave lengths, thus making you see color.