Why I see a purplish tint in my blue sapphire?

Many sapphire gemstones have an undertone or non-dominant colour tone. Especially darker colours like royal blue can have a purplish or violet undertone. When this secondary colour becomes so obviously distinguishable in different light conditions, the sapphire is also called a colour changing sapphire.

Sapphires when observed in the daylight show the true colour of the gemstone. When you observe them indoors under yellow artificial light, you can get a slight purplish tint in them.

However, this purplish tint is no closer to a real purple sapphire. Watch this video showing a comparison between a blue sapphire and a purple sapphire.

_{A Blue Sapphire Ring and a Purple Sapphire}

_{Gemlightbox's colour controls allow us to observe sapphires in different colour conditions}

_{When the Yellow light is on the blue sapphire turns slightly purplish and when it off turns blue again}

A blue sapphire solitaire engagement ring