Gemstone ID question

 I recently purchased a gemstone and am in a quandry of just what
exactly it could be. <snip> In incandescant light it is deep
purple red, and in natural light it is Tanzanite blue <snip>  Sue 

Hi Sue. You’re right in that you’ve never seen a kunzite which is
blue. Kunzite is the variety of spodumene that is pink in color. The
pink color itself is what gives it it’s variety name. Also, anything
can occur in nature, but most color-change stones, such as
alexandrite, sapphire and garnet usually look red (or reddish) in
incandescent light, and green (or greenish, not blue or bluish) in
natural daylight, hence the phrase “Emerald by day, Ruby by night”.
The most likely answer is that the stone in question is probably a
type of color-change manufactured glass that is sometimes marketed as
"alexandrium" or even “zandrite”. There are other possibilities as
well. I agree that you might be better served by having a qualified,
experienced gemologist perform an ID instead of an appraisal. If it
turns out to be a natural color-change stone, an appraisal could be
worth it. The gemologist would probably offer this service if it
turns out to be a natural gem. I hope it winds up being worth a
fortune for you! Warm regards, James