If you are wondering why those neon signs vary in colors, it is because these signs are created in three different ways using three different gases. Some use inert gas, for example- a combination of neon and argon/mercury gases. While neon gas glows in reddish-orange color, argon and mercury lights give off a light blue color. Some neon light also use fluorescent powders.
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A Prelude to Neon Signs Advertising
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