How-To Tuesday: How to Make Medieval Ink

Posted by E.H. Kern

In this week’s How-To Tuesday we are going medieval. We are making our own black ink using a recipe from thirteenth-century France.

Looking at the golden inlays and the red and blue ink of a medieval manuscript, it is easy to understand why these books were so expensive to make. But most of the text was written using black ink, which at first glance doesn’t seem to be very expensive. However, the black ink was exclusive as well. It took time to make and the ingredients had to be imported from far away.

The black ink that was used in medieval Europe is called iron-gall ink. There are hundreds of recipes for making iron-gall ink, but they have a few things in common. These things are gallnuts, iron vitriol (a. k. a. copperas), and gum arabic. Many recipes also use rainwater and wine.

A gallnut is the swelling of the bark on a tree after an insect has laid its eggs inside the bark. To make iron-gall ink, the gallnut from the gall wasp is used. The wasp lays an egg in the bud of an oak tree. Around the larva a round sphere—the gallnut—begins to form. When the larva is a fully developed wasp, it bores a hole in the gallnut and flies away. With the wasp gone, the gallnut is harvested for making ink. The finest gallnuts came from Aleppo in present-day Syria.

Iron vitriol is made from ferrous sulfate, a mineral that today is mostly used to treat iron deficiency and anemia. The go-to place for this ingredient was Spain.

Gum arabic is the harvested and dried sap from the acacia tree. During the Middle Ages, gum arabic was imported from Asia Minor in present-day Turkey or Egypt.

When all of these ingredients are mixed together the tannic acids of the gallnuts react with the iron vitriol and the concoction turns to black. Not only that, the acids from the gallnuts make the ink sink into the writing surface and stick. Gum arabic is added as an adhesive to make the ink stay on the quill.

At the British Library, there are several manuscripts with recipes for making iron-gall ink. This particular recipe is from the thirteenth century and has been translated from the medieval French.

Okay, let’s make some ink!


Preparation time: Approximately three days.

1. Take a jar and fill it with eight pounds of rainwater.

2. Add half a pound of small gallnuts and crush them.

3. Put the jar on the fire and boil until the water with the gallnuts is reduced by half.

4. Take three ounces of gum arabic and grind it.

5. Add the gum to the mixture.

6. Boil until reduced by half again and remove the jar from the fire.

7. In a separate jar, take four ounces of vitriol and one pound of warm wine and mix them.

8. Add the mixture little by little to the ink while stirring.

9. Leave to rest for two days.

10. After the two days, stir the ink everyday four times with a stick.

Enjoy… or just go out and buy a ballpoint pen.