A method for demonstrating the immiscibility of two or more liquids, wherein each liquid exhibits a different colour, the method comprising:I. providing a first colour formulation, wherein the first colour formulation comprises a hydrophilic phase, a first colourant and an alkalising agent; II. providing a second colour formulation, wherein the second formulation comprises a hydrophilic phase, a second colourant and an alkalising agent; III. providing a thickening formulation, wherein the thickening formulation comprises thickener capable of interacting with the hydrophilic phase and capable of undergoing hydrophobic-hydrophobic interactions; IV. mixing the first formulation with the thickening formulation to form a first liquid exhibiting a first colour and mixing the second formulation with the thickening formulation to form a second liquid exhibiting a second colour; and subsequently V. applying the first liquid and second liquid next to each other in or on a receptacle; and subsequently VI. agitating the receptacle; and subsequently VII. observing the immiscibility of the first liquid and the second liquid; VIII. comparing said receptacle with a control demonstration where said liquids are substantially free of said thickener.