Neodymium glass is Alexandrite , you are correct Sue :thup:....just different names for the same thing.
Also Neodymium glass only has one colour change..pinkypurple to blue.
It is neon light and the new energy saving bulbs that give the blue colour, whilst daylight and the normal incandescent light bulbs give the pinkypurple colour.
The intensity of the colour change and depth of colour depends on the quantity of the precious earth metal neodymium added to the molten glass, and of course, the thickness of the glass itself.
It is different rare earth metals that give the other colour changes....John is currently checking the specific ones so I can pretend I knew all along!! They are not called Neodymium Glass nor Alexandrite.......back with more info when I have found out for you! :hi: