Chromatography with coffee filters 🌈 age 3-8 🌈 This simple experiment explores the concept of chromatography (separating mixtures). All you need are white coffee filters, non-permanent markers (we used Mr. Sketch) and water. Draw a circle in the middle of the filter (black works best), fold 3 times and place the tip in the jar of water. Watch the colors spread. We tried black, purple and brown and only black really worked for us, but it probably depends on the markers you use. 👍🏻