While the term "neon sign" implies that only neon is used, other noble gases are also employed to create different colors:

* Helium: Produces a pale yellowish-white light.

* Argon: Emits a bluish-purple glow.

* Krypton: Produces a whitish light.

* Xenon: Generates a bluish-white light.

These noble gases are used individually or mixed together to create a variety of color combinations in neon signs.