F-centers can be produced from carbon crystals by exposing them to ionizing radiation, such as X-rays, gamma rays, or UV light. This causes cation vacancies and free electrons to be generated within the crystal lattice. Alternatively, F-centers can be introduced intentionally through chemical doping of the crystal with impurities, such as metals or metalloids.

F-centers are also present in many other organic gems, such as diamonds, rubies, and sapphires. In these gems, the F-centers are usually created by the presence of impurities, such as nitrogen and hydrogen, which can create lattice defects that trap electrons. The presence of F-centers affects the color of these gems, giving them the characteristic hues that are associated with them. Additionally, the presence of F-centers can also affect the gem's optical, electrical, and thermal properties.
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