Combine milk, washing-up liquid and food colouring for this amazing effect... Add a layer of milk, then add drops of food colouring in different spots around the centre. Add one drop of washing-up liquid into the centre of the mixture OR (as in this video) prod the centre with a cotton bud with washing-up liquid on the end. [From @GE via @SarahBearchell] The science behind it is explained here: http://www.youtube.com/watch?v=hPFwDaR1g70
River of Five Colors/ Caño Cristales in Columbia.Caño Cristales is a Colombian river located in the Serrania de la Macarena, province of Meta. aka "The Liquid Rainbow" or even "The Most Beautiful River in the World"
Caño Cristales (Colombia) - Caño Cristales is a Colombian river located in the Serrania de la Macarena province of Meta. The river is commonly called "The River of Five Colors" or "The Liquid Rainbow," and is referred to as the most beautiful river in the world due to its striking colors. The river appears in many hues–including yellow, green, blue, black, and especially red–which are caused by the Macarenia clavigera (Podostemaceae) at the bottom of the river.