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Old 26th Apr 2021, 6:56 pm   #32
broadgage
Nonode
 
Join Date: Jan 2010
Location: North Somerset, UK.
Posts: 2,129
Default Re: Crompton 60W bulb

Back in the day, lamp makers offered "natural coloured" lamps. This referred to lamps made of coloured glass rather than clear glass lamps coated internally or externally with paint etc.

The red lamps were more expensive than other colours, this because red glass contains gold, in contrast to the base metal compounds used for other colours.

In the days before good quality fire resistant colour filter materials, much use was made of natural coloured lamps for theatre lighting.
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