I would like to make a mixture of two immiscible (insoluble) liquids -- like oil and water. The point, however, is to use two contrasting colors for a visual display.
Ideally, the less-dense liquid would be colored or dyed black, while the other, denser liquid would be of a lighter color.
My first thought is to use some form of petroleum. I know there are oil dyes used in engines, but I'm not sure if those would also spread to water if mixed.
In any case, it would just be nice to have a very dark surface liquid suspended above some water or other bright/clear liquid.
Thanks!