Marbling, whether of the infant playgroup or of the fine bookbinding variety uses the technique of flotation-printing, i.e. of floating colours onto a prepared solution of a water-based thickener ^[1]. If you are interested in trying this art/craft check the internet for materials & techniques (there are many and various ways of producing interesting work on both paper and fabric).

The examples presented here derive from floating dilute oil-colours onto a thin cellulose gum – the resulting patterns (whether simply cumulative or stirred can be lifted by carefully laying a piece of paper on the surface.

My own experience of this technique goes back to the 1960s when I was involved in a workshop, Koraz, that produced wall-sized marblings for interiors. Since that time it has been an occasional diversion (rather than the obsession that it can become. Beware).

^[1] The tradition method for this uses Carragen Moss, but commercial methylcellulose gums offer a cheaper alternative these days.