text: Certain household materials and substances can be seen to exhibit the property:
  * Ordinary pressure-sensitive tape ("Scotch tape") displays a glowing line where the end of the tape is being pulled away from the roll. Soviet scientists observed in 1953 that unpeeling a roll of tape in a vacuum produced X-rays.  The mechanism of X-ray generation was studied further in 2008. Similar X-ray emissions have also been observed with metals.
  * Opening an envelope sealed with polymer glue may generate light that can be viewed as blue flashes in darkness.
  * When sugar crystals are crushed, tiny electrical fields are created, separating positive and negative charges that create sparks while trying to reunite. Wint-O-Green Life Savers work especially well for creating such sparks, because wintergreen oil (methyl salicylate) is fluorescent and converts ultraviolet light into blue light.
  A diamond may begin to glow while being rubbed; this occasionally happens to diamonds while a facet is being ground or the diamond is being sawn during the cutting process. Diamonds may fluoresce blue or red. Some other minerals, such as quartz, are triboluminescent, emitting light when rubbed together.
  Triboluminescence as a biological phenomenon is observed in mechanical deformation and contact electrification of epidermal surface of osseous and soft tissues, during chewing food, at friction in joints of vertebrae, during sexual intercourse, and during blood circulation.
  Water jet abrasive cutting of ceramics (e.g., tiles) creates a yellow/orange glow at the point of impact of very high-speed flow.