Diamond Polygon, Blue (Teal) Cut Faceted Alexandrite & Emerald Polygon.
An Alexandrite is a gemstone that changes color in sunlight, ie. from purple to teal (green-blue). It was originally discovered in Russia, in the 18-19th Century. It is very rare in its natural state. Here is some Abstract Surreal Art created by myself, displaying this gemstone:
Left: Alexandrite Sphere, and Cylinder. Right: Emerald Green Triangular Column.