Paper marbling is a method of aqueous surface design, which can produce patterns similar to smooth marble or other stone. The patterns are the result of color floated on either plain water or a viscous solution known as size, and then carefully transferred to an absorbent surface, such as paper or fabric. Through several centuries, people have applied marbled materials to a variety of surfaces. It is often employed as a writing surface for calligraphy, and especially book covers and endpapers in bookbinding and stationery. Part of its appeal is that each print is a unique monotype.
There are several methods for making marbled papers. A shallow tray filled with water, and various kinds of ink or paint colors are carefully applied to the surface with an ink brush. Various additives or surfactant chemicals are used to help float the colors. A drop of “negative” color made of plain water with the addition of surfactant is used to drive the drop of color into a ring. The process is repeated until the surface of the water is covered with concentric rings. The floating colors are then carefully manipulated either by blowing on them directly or through a straw, fanning the colors, or carefully using a human hair to stir the colors.
The method of marbling most familiar worldwide is made on the surface of a viscous mucilage, known as size or sizing in English. This method is commonly referred to as “Turkish” marbling, the term “Turkish” was most likely used as a reference to the fact that many Europeans first encountered the art in Istanbul. The form of marbeling, Turkish marbeling, as most-widely known today is believed to have been derived from the form practiced in Turkey. Although, there are similar, but lesser-known, forms made by Persian, Tajik, and Indian people.
Historic forms of marbling used pure pigments mixed with water for colors, and sizes were traditionally made from gum tragacanth (Astragalus spp.), gum karaya, guar gum, fenugreek (Trigonella foenum-graecum), fleabane, and psyllium. Since the late 19th century, the carrageenan-rich alga known as Irish moss (Chondrus crispus), has been employed for sizing. It has been suggested that False Irish Moss (Mastocarpus stellatus) was also used, although this substance has not specifically mentioned in historic literature.
Today, many marblers use powdered carrageenan, extracted from various seaweeds. But buying and cooking briefly in water the emptied packages of carrageen moss sold in Ireland for eating at breakfast is far cheaper and just as effective. Another plant-derived mucilage is made from sodium alginate. In recent years, a synthetic size made from hydroxypropyl methylcellulose, a common ingredient in instant wallpaper paste, is often used as a size for floating acrylic and oil paints.
In the sized-based method, colors made from pigments are mixed with a surfactant such as ox gall. These are then spattered or dropped onto the size, one color after another, until there is a dense pattern of several colors. Straw from the broom corn was used to make a kind of whisk for sprinkling the paint, or horsehair to create a kind of drop-brush. Each successive layer of pigment spreads slightly less than the last, and the colors may require additional surfactant to float and uniformly expand.
Once the colors are laid down, various tools and implements such as rakes or combs, are used in a series of movements to create more intricate patterns. Paper or cloth, often mordanted beforehand with aluminium sulfate (alum) is gently laid onto the floating colors (some traditional methods such as Turkish ebru do not require mordanting beforehand). The colors are thereby transferred to the surface of the paper or material.
If necessary, excess bleeding colors and sizing can be rinsed off, and then the paper or fabric is allowed to dry. Not mentioned in books, but observed among Florentine paper marblers is the method of dragging the sheet of paper over a rod to draw off the excess carrageen moss base. After the print is made, any color residues are carefully skimmed off of the surface of the size, in order to clear it before starting a new pattern.
Contemporary marblers employ a variety of modern materials, some in place of or in combination with the more traditional ones. A wide variety of colors are used today in place of the historic pigment colors. Plastic broom straw can be used instead of broom corn, as well as bamboo sticks, plastic pipettes, and eye droppers to drop the colors on the surface of the size. Ox gall is still commonly used as a surfactant for watercolors and gouache, but synthetic surfactants are used in conjunction with acrylic, PVA, and oil-based paints.