Dear Karen and all on Orchid,
My GIA training indicates that alexandrite is the color change
variety of the mineral species chrysoberyl, so yes, all alexandrite
should color change to some degree. Some stones you have to try
really hard to see the change, and ,I must say, I have seen some
material that is misrepresented, in my opinion, as the color shift
is for all practical purposes not apparent. Remember to look for the
change under different lighting sources, as fluorescent lighting
brings out the blue/green color, and incandescent brings out the
purplish/raspberry color.
I’m not sure about the percentage thing; I didn’t run into that in
my searches. Hopefully someone else will chime in on that part. When
I was looking to replace a specific stone, I would ask which color
was most dominant (usually the greenish color), how pure the color
change was, and to describe as best they could the purity of the
colors.
Take care all. Hope everyone is having a busy but happy season, and
looking forward to spending a little more time at home with
families. We have an additional 2 inches of snow from last night and
35 mile an hour winds today. Brrrrrrr.
Happy holidays.
Brenda
david lee jeweler
Mason City, Iowa 50401