A sample of the compound 'rubrocurcumin', synthesized from boric acid, curcumin tumeric extract, and oxalic acid in boiling acetone as an Honors Chemistry II activity.  I was interested in the color:  some references claimed it was red, while others claimed it was green.  It turns out it's both!  Depends on the angle of the light!  It transmits red light and reflects green light.