This is an exceptional quality Chatoyant Russian Charoite.
Dimensions are - $40 x 30 x 5 mm.
The back is not polished. It has a slight bevel to facilitate stone setting.
I have many of those stone and they came from the same large piece of material.
I am in the process of cutting some designer shapes which will be posted in the near future.
I also have some fair bit larger Charoite stones.
Please inquire with your needs.