THE METHOD AND SYSTEM FOR DRAWING ON SHEEP PARCHMENT AND ON PAPER,1 AND SHADING WITH WASHES. CHAPTER X
[…] And you may likewise work and shade with colors and with clothlets 2 such as the illuminators use; the colors tempered with gum, or with clear white of egg well beaten and liquefied.
The craftsman’s handbook by Cennini, Cennino, active 15th century; translated by Thompson, Daniel Varney, 1902- ed
CHAPTER II. On the liquids with which colors are tempered to fix them on paper.
The liquids with which colors are fixed are these: namely egg white and egg yolk from chicken, gum arabic and gum tragacanth, dissolved in clear spring water. Sometimes, to soften them, honey water, or sugar water, or candy water is necessary, as I will explain in detail, God willing, when speaking of their preparation.CHAPTER IV. On white.
I have found only one white color good for the art of illumination, that is lead white or otherwise cerussa; because white extracted from burnt bones, being too pasty, does not work. Nor is it useful here to explain the method of making cerussa, it being almost universally known that it is made with lead and is found abundantly everywhere.De arte illuminandi (Libellus ad faciendum colores), 14th century, in Sui colori degli antichi, Introduzione, parte prima : Dalla remota antichità al secolo 14. ; De arte illuminandi by Guareschi, Icilio
How to make white body color (biacca)
Water colors and gouaches were prepared to work on parchment and paper. The main binders were white of egg, also called glair, and/or gum arabic. Segreti per colori [Secrets of colours], an early 15th century treaties on colors and illumination, gives tens of color recipes of colors and binding media that best fit them, sometimes suggesting different binders for different uses of the same color. Below are a few examples:
65. How to grind azure to use with the pen and in body colour. […] And if you wish to use it with the pen or for miniatures, take the azure and distemper it with glue made from parchment clippings [gelatin/rabbit glue], or with gum water and prepared white of egg, and it will do well.
105. To make a splendid yellow, finer than orpiment or German giallolino […] Distemper it with clear ley [water mixed with ashes used for washing], and an equal quantity of prepared white of egg, and with powder of gum arabic, and let it remain together for two nights.
226. To prepare white lead for painting —Take the white lead, and wash it several times in hot water, and then take two grains of clear gum-arabic and 3 grains of white incense, grind them very well with a little clear water, and then add the washed white lead, and grind the whole together, and collect it and add to it as much gum-water as you think it will bear, and if it is too hard put a little fresh water to it, and it will do well.
Secrets of Colors (Bolognese Manuscript), first half of 15th century, Mary P. Merrifield, Medieval and Renaissance treatises on the arts of painting : original texts with English translations
To make a white gouache for drawing highlights, Cennino Cennini suggests using lead white (called biacca in Italian) mixed with two different binders. First he advises to use gum arabic to work with a dry brush in body color; and in the next chapter he suggests the usage of egg yolk to work with liquid medium (washes):
HOW YOU SHOULD DRAW AND SHADE WITH WASHES ON TINTED PAPER, AND THEN PUT LIGHTS ON WITH WHITE LEAD. CHAPTER XXXI
[…] When you have got this done, take a little white lead well worked up with gum arabic. (I will explain this to you later on, how this gum is to be dissolved and melted; and I will explain about all the temperas.) Ever so little white lead is enough. Have some clear water in a little dish, and moisten this same brush of yours in it; and rub it over this ground white lead in the little dish, especially if this is dried up. Then dress it on the back of your hand or your thumb, shaping and squeezing out this brush, and getting it empty, practically draining it. And begin rubbing the brush flat over and into the areas where the high light and relief are to come; and proceed to go over them many times with your brush, and handle it judiciously.
Then, for the accents of the reliefs, in the greatest prominence, take a pointed brush, and touch in with white lead with the tip of this brush, and crisp up the tops of these high lights. […]
HOW YOU MAY PUT ON LIGHTS WITH WASHES OF WHITE LEAD JUST AS YOU SHADE WITH WASHES OF INK. CHAPTER XXXII
The craftsman’s handbook by Cennini, Cennino, active 15th century; translated by Thompson, Daniel Varney, 1902- ed
I advise you, furthermore, when you get to be more experienced, to try to put on lights perfectly with a wash, just as you do the wash of ink. Take white lead ground with water, and temper it with yolk of egg; and it blends like an ink wash, but it is harder for you to handle, and more experience is needed. […]
As you can see, Renaissance artists were very aware of various properties of colors and binding media they were using and knew when one binder or pigment would work better then the other. This is one of the reasons why it is very difficult to simulate the depth of color, variations of tone and texture we can see in some Renaissance painting masterpieces with colors “out of the tube” which components remain unknown as they represent a trade secret.
Let’s do some Alchemy!
White gouache ingredients:
GUMMA
Gum Arabic is a hardened sap of acacia tree. It can be powdered and dissolved in water [N.B. saps that can only be solved with help of solvents are called resins] to make a solution with adhesive ability that can be used in many ways.
Gum arabic was very widely used in past to make color binders, dyes and gilding boles. Today it is still used for drawing, painting, photography, printmaking and even in food industry.
OVUM
Since the very early days of our civilization eggs are used in a variety of fields. In art, each part of the egg has its particular uses:
- Egg yolk is mainly used as binder to work on panels and to make emulsions
- Egg white (also know as glair) is used as binder to paint on parchment and paper, it creates a very hard and shiny veil and thus sometimes white of the egg was used as varnish
- Egg shells, rich with calcium, were also powdered and used as an additive to colors or even as pure pigment.
CERUSSA
White lead (lead carbonate), artificially produced since the times of ancient Greeks and probably even earlier, or its mineral near equivalent cerussite were until quite recently very commonly used in painting of any kind and medium, all branches of industry and even cosmetics.
Unfortunately, the toxicity of this pigment has led to severe trade and production restrictions and this pigment is now largely replaced by zinc an titanium whites.
AQUA
Clean water, typically rain or spring water was used. We will use distilled water.
Additional ingredients:
- Honey or glycerin: to make the color denser, improve viscosity and make it more elastic, honey or glycerin is sometimes added.
- Preservative: vinegar, wine, cloves essential oil, or today you could also use a chemically produced biocide such as Nipagina (Methylparaben) or Phenol. If you do not intend to store the color preservative is not necessary.
- Chalk: calcium carbonate is often added to pigments as a filler when creating opaque gouache colors.
Recipe:
A very basic recipe could be as simple as mixing gum arabic or purified egg glair with powdered pigment, but the following more complete and functional medium is based on the 14th-century medieval treatise on manuscript illumination known as De Arte Illuminandi:
CHAPTER XXXI. Special rule for making very excellent gum for illuminating letters both with the brush and with the pen.
First prepare egg white with the sponge, as was said; then gum water, as was explained above; and, subsequently, honey water, dissolving in the said water as much candy sugar as this water can dissolve. Then take one part of gum and another part of egg white, mix them together in the bottle introducing a part or less of honey water with sugar, and let them stand together thus. When they have clarified, colors are fixed most beautifully with such a tempera, if the artist knows how to use it. And note that it is better to put less honey water than other parts of the other substances; and the reason is that, if too much were put, it would immediately dissolve into watery humor; if too little, the colors would immediately crack. In this everyone must take care to get the right tempera. […]
De arte illuminandi (Libellus ad faciendum colores), 14th century, in Sui colori degli antichi, Introduzione, parte prima : Dalla remota antichità al secolo 14. ; De arte illuminandi by Guareschi, Icilio
This medium allows you to create a white paint that can be diluted for washes or applied thick to create crisp hatched lines. The only disadvantage, as it uses organic materials (primarily egg), is its very short shelf life (about one month if refrigerated).
Ingredients:
- Titanium white
- Egg
- Gum arabic
- Distilled water
- Honey or sugar
- Optiona: clove essential oil
Step 1: Prepare the egg glair
Beat egg white into a froth and set aside for 1-2 hours. Then separate the foam from the liquid deposited at the bottom by gently pouring the liquid into a different container. Read more about preparing egg glair.
Step 2: Prepare gum water
Take 1 part of gum arabic powder and 2 parts of distilled water. Powdered gum arabic dissolves in water fairly easily. To speed the process, warm it in a water bath (bagnomaria), but it is best to just leave it overnight and let it dissolve naturally.
Step 3: Prepare honey water
Mix honey and distilled water in equal proportions and boil until the volume reduces to the original amount of honey or less. Let cool. You can substitute honey with saturated sugar solution.
Step 4: Make the medium:
- 1/3 Gum solution
- 1/3 Egg white
- 1/3 (or less) Honey water
- Add a few drops of clove essential oil, it will increase shelf life a little bit.
Shake the solution to mix the ingredients very well.
Step 5: Add binder to the pigment:
For the white gouache in chiaroscuro drawing on toned paper, it is advisable to grind titanium white pigment directly with this binder to a tooth paste consistency, put in a container and dilute when needed with water. Keep the container well sealed and refrigerated.