Bohemian Alexandrite Decanter and Ashtray

This is an alexandrite Bohemian Decanter and Ashtray that I bought for almost nothing at a garage sale. They looked beautiful in the sunlight. The decanter is 11" x 4.25" including the stopper. The stopper on its own is 4.5" x 2". The ashtray is 4.75" x 2". The decanter is a triangle.
By day, these two pieces are lavender and at night they turn blue.