All sapphires color change under different lighting?

[OTL]

I just got an unheated cornflower blue sapphire verified from AIGS. The color is cornflower blue under cool daylight. But it goes purple and violet under fluoresent light, looks like a violet tanzanite. Seller didn't mention it is a color change sapphire.

So I'm just wondering does all sapphire color change under different lighting? Or it is normal, I shouldn't put the color change label on it?
Further more, does the color change decrease the value of a sapphire?

 

[chrono]

It is normal for sapphire to shift under different lighting, which is why I always recommend checking the stone out both indoors and outdoors. When the shift is very strong, pronounced and complete, it is called a colour change / shift (you'll get plenty of opinions here as to what constitutes a shift and what is a change. ) Sometimes the shift is to a muddy or gray or drab colour. Sometimes the shift is to a pretty colour.

 

[OTL]

It is normal for sapphire to shift under different lighting, which is why I always recommend checking the stone out both indoors and outdoors. When the shift is very strong, pronounced and complete, it is called a colour change / shift (you'll get plenty of opinions here as to what constitutes a shift and what is a change. ) Sometimes the shift is to a muddy or gray or drab colour. Sometimes the shift is to a pretty colour.

Thanks, I guess my sapphire is normal, not a color change one. if it is, AIGS will probably have it stated under comment. Luckily it shifts to a violet Tanzanite color, a pretty color shift to me.