• Violet Shirran

Making Black ink with Oak Galls.


Today I'll be talking about making Oak gall ink , a rich dark ink in use since medieval times.

Oak Galls or Oak marble galls are found on many species of oak trees. These round wood like marbles grow in clusters and are caused by the Oak gall wasp. The wasp lay its eggs on the tree and the chemical emitted caused the tree to form a protective layer around the eggs, giving it shelter from the rain and predators.


The reason people are so interested in them is that they are high in Tannins. The function of tannins is to put off predators , its astringent taste makes it bitter and is the causes bitterness in Teas, coffee, red wine and some unripe fruits. Pomegranates, most berries, nuts, tree bark, red and black beans and some herbs and spices like cinnamon and thyme all contain tannins.

Tannin gets its name from the Medieval Tannore, oak bark and refers to the use of oak bark to tan leather.

The reason I use tannins is to make a dark ink or to use in natural dyeing.

Making ink and natural dyeing are closely connected and is the reason I have started experimenting with ink..... most things that make a good dye also make good ink.

Oak gall ink or iron gall ink has been used since medieval times and was prized because it is permanent, dark and waterproof.


So let's get started....

What I used to make oak gall ink were Oak galls, Iron water and gum arabic. I also used a spice grinder but you can use a hammer to smash the galls. You will need a large jar and some smaller jars to put your ink in and they should all be sterilized. Iron water is simply made by putting a piece of

rusty metal, like old nails, into a container with vinegar and left to soak.


Oak galls are pretty tough so if you are not using a spice grinder put the galls in a cloth bag and smash them with a hammer. The finer the powder the better.






Next, put the gall powder in a jar with rainwater ( I used about 4 table spoons of powder and 500ml of rainwater.)

Leave the powder to soak for a few days until the tannins have leached into the water and you have a nice tan colour.

You can also heat the water and gall powder if you like and then leave to soak. ( Try both methods and compare the results. )

Next sieve the liquid using muslin, a fine sieve or a coffee filter.




I then mixed the liquid with Iron water ( I used about 4 table spoons of powder and 1 1/2 to 2 teaspoons of iron water.)


The mixture immediately darkens when you add the iron water but the real magic happens when you use your ink, as it dries and oxidises it becomes a lovely rich black.








I added a teaspoon of gum arabic which give a gloss and helps it flow.

Store you ink in sterilised jars ( You can sterilise your jars with boiling water or pop them in a hot oven. )









Now the fun starts, you can use your ink in your art or for calligraphy as it has been used since medieval times.... enjoy.