Thursday 23 September 2010

Walnut Ink





Making Walnut Ink

By Madame Elizabeth de Nevell, CW


The Walnut Tree

Walnuts have been recognized as one of the oldest tree foods known to man, dating back to about 7000 B.C. Considered food for the gods in the early days of Rome, walnuts were named "Juglans regia" in honor of Jupiter. The black walnut is a hardwood tree that frequently grows to a height of one hundred feet with a trunk diameter of up to six feet. The dark, rough bark, is divided into squarish units. The leaves are alternate, one to two feet long, and have fifteen to twenty three leaflets that are light green in color. Today, they are commonly called "English" walnuts, in reference to the English merchant marines whose ships once transported the product for trade to ports around the world. Also known as the Persian Walnut (attributed to the region of it’s origin), the Black Walnut grows in many parts of North America, as well as throughout Europe.

When used for making dyes and ink the benefits of walnut are twofold. The Walnut tree produces a substance known as juglone (5-hydroxy-alpha-napthaquinone) which is highly toxic to many other plants and some animals. Awareness of black walnut toxicity dates back at least to Roman times, when Pliny noted a poisoning effect of walnut trees on "all" plants. Juglone is the source of the dark color in walnut hulls. Initially colorless, juglone oxidizes over time to a very dark brown. In addition to the juglone, the husk of walnuts, like many plants, contain tannins. Ionic iron combines with tannins to produce iron tannate compounds, which are black, and the basis of gall inks. The juice from walnut husks was used extensively throughout history as a dye, it is colorfast, lightfast and virtually no solvent removes it from skin.