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Four versions of ink made from oak galls

This article is based on the documentation for the ink as entered at the Kingdom Arts and Science Fair in Aarnimetsä. The entry consisted of the four different samples of ink and a sheet of text written with the ink to test its lightfastness. T he entry won the prize for best documentation.


These inks were made form oak galls gathered last Autumn. Oak gall is a small ball wicht appears on the leaves and branches of oak trees. It is the result from a "bite" of a small insect, the insect injects a poison into the tree. This poison triggers a defensive reaction. This reaction causes a smaal amount of "tree" to form around the bite. The insect uses this to lay an egg in, and the larvae hatched from this eggs lives in the growth (the insect leaves the ball before autumn). Since we found that the galls on the leaves were different from those on the bark, we’ve made separate samples from both kinds.

Our starting point was the recipe in Compleat Anachronist #43, which calls for equal amounts of ground galls and water, boiling, and then leaving the mixture to ferment for a few months.

As we were gathering the galls we got into conversation with a passer-by who made ink himself and said he used one ground gall to a glass of water, added a rusted nail and waited a few weeks. The addition of oxidated iron was confirmed by Michelle Brow n, who writes specifically about medieval ink and the Merck Index, which is a standard reference in chemical science, and so we decided to try samples with and without iron.


We have crushed the galls and added hot water until they were covered. The jars were then heated au bain marie (since we didn’t have a non-food pan of the right size) at about boiling point for 10 minutes. After about three months we drained the ink fr om the molded galls. This could have been done earlier, but we didn’t get around to it...


When we drained the inks, there was a significant difference between the iron and non-iron samples. The non-iron ones were coloured orangish and you could see through them. The ones with iron were black. The leaf galls seem to have come out better than the bark ones, but only a little.

When I started writing the samples to see how the inks did in the light, the non-iron samples came out a lot better than expected. We think this is caused by the fact that I wrote with a metal nib, which may have been a bit rusted. I’ve put on dots wit h a finger, and those did not color up darkly like the written bits. I believe the non-iron inks have also colored up a bit in the jar, making the sample that was not put in daylight which was written two weeks later than the first a bit darker..

On the whole, the inks do seem to be light fast after three weeks out in the sun, allthough we’ll leave them out for a few more weeks to be sure. They actually seem to have gotten darker than they were at first. We’ve heard the suggestion that medieval ink actually got darker after being used from others as well.


A friendly passer-by in the woods

Megan ni Laine de Belle Rive, A Palette of Period Pigments, Compleat Anachronist 43, may 1989.

Understanding Illuminated Manuscripts, Michelle P. Brown, A guide to technical terms, The J. Paul Getty museum in association with the British Library, 1994.

Merck Index, ed. P. Stecher, A book containing over 40,000 names and descriptions of chemical compaounds, published by Merck & Co.

Copyright © Written in January 1998 by Lord Floris van Montfort and Lady Hannah of Hanecnolle, who can be reached at or