Plasticine clay is the trademarked name for a non-toxic oil-based clay used in stop-motion animation, sculpture and free play. Plasticine is similar to polymer clay in its ability to form realistic shapes and textures, but different because it won't dry when baked in an oven. If you need a non-drying clay for your artistic endeavours, you can make your own Plasticine-like clay with common ingredients.
Tear the wax into 1-inch pieces.
Add the wax, petroleum jelly and mineral oil to the top of a double boiler. Melt the mixture over medium heat, stirring constantly with a wooden spoon.
Stir in the lime once the mixture is completely liquefied. Stir until smooth.
Remove the mixture from the heat and separate it into bowls, one for each colour.
Add a few drops of food colouring to each bowl and mix it into the clay to make different colours.