I often hear my students lament about how if only they could travel to the rainforest they would find something really interesting to photograph. I tell students “look around where you live – there are wonderful things to photograph everywhere”.
Many materials show internal stress when illuminated with polarized light and photographed with a second analyzing polarizer. This unique property of materials is called birefringence. Some of the more common material that exhibits this property is glass, ice, and most plastics.