This video uses a seeded boundary technique to visualize water mixed with mineral oil. The author utilizes both water and oil dyes of various colors to highlight the boundary between the layers that result from differences in polarity and density of each base fluid. What stood to me was how vivid the mixture turned out, and how many intricate shapes and patterns presented themselves on the dish!
Video is by Steve Pavlovsky of Liquid Light Lab on YouTube, whose website can be accessed here: http://www.LiquidLightLab.com