BT604 Chrysoberyl var. Alexandrite
A nice nearly complete alexandrite sixling on a bit of matrix, making for a superbly well balanced thumbnail/ toenail sized specimen.
In real life, the color is a dark green-- for whatever reason, the combination of the Alexandrite's optical properties and the camera's sensors makes it appear light purple. In sunlight or under a daylight equivalent bulb, it will appear a more crisp grass green, then duller green to purple (especially near the very top) under incandescent. The color change to purple is not visible on the whole specimen, despite what the images show.
This is a very beautiful miniature, and the recent finds at this location have actually make a sixling alexandrite fairly obtainable-- in previous years good examples were nearly impossible to find (except from Brazil, though the quality has never been quite as good) and always prohibitably expensive. This isn't exactly cheap either, but compared to what you might pay for a Russian example of lesser quality, this is quite good.
NOTE: the final image with the stark color contrast will NOT be observable with your naked eye. This was done by shining a daylight equivalent LED on the piece, while lighting from a different direction with an incandescent bulb. The camera only picks up the purple (which is really a dark purplish green to the naked eye) while the LED brings out the crisp green on the upper half of the specimen. You will be able to see the green if you use a dalight equivalent bulb, but not the lavender/ purple.