These solid pieces of glass have coloured acrylic sheets stuck to their faces. When angled just right, a bunch of new colours are created!
It is called a CMY Cube because the acrylic sheets are Cyan, Magenta, Yellow. These colours are similar to RGB (Red, Green, Blue) but work in the opposite manner. They are subtractive (not additive) colours. Take a look at the diagram in the photo above to get a better understanding.
