Marbling, or ebru, is one of the most popular forms of Turkish art for centuries can produce patterns similar to smooth marble or other stone.
Basically, you drip paint on top of water, use needles and brushes to make swirling designs, and then transfer the finished work onto paper. The paints are treated with a surfactant, called ox gall, to lower their surface tension, allowing them to float, and the water’s properties result in fluid, hypnotic patterns. Sometimes, oil or turpentine may be added to a color, to achieve special effects. The colors are then spattered or dropped onto the size, one color after another, until there is a dense pattern of several colors.