How to Make Oak Galls Ink: Traditional Easy Oak Gall Ink Recipe That Really Works! Make Your Own Ink

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Oak gall ink is easy to make and is real, actual ink. My recipe for oak galls ink is based on a historic recipe from the 1660s and was in use long before that. Forget all the chemical-laden inks. You don’t need them. This is a fun project to tackle any time and it’s not just an experiment – you’ll be able to actually write with and draw with the end product – actual ink!

You can use oak (or iron) gall ink with cartridge pens, quill pens, glass pens, and more. Create your ink drawings, practice your calligraphy, or just write your grocery list using the same ink they used to write the Magna Carta, Chaucer’s Canterbury Tales, and the Declaration of Independence.

What Are Oak Galls?

Oak galls, or oak apples, are the dried out remains of oak galls in which wasp eggs hatched. A gall wasp injects an egg into the underside of an oak leaf. To protect itself, the tree produces tannic acid and gallic acid to surround and encapsulate the developing larva. This creates a round, apple-like tumor known as an oak gall.

Once fully developed, having feasted on the contents of the gall, the juvenile wasp eats a hole through the outer wall of the gall and escapes. It’s at this point that you want to harvest the galls or oak apples.

The hole from which the wasp emerged is clearly visible on each gall nut, so harvesting them is easy. And once dried, they’re ready to use in your ink recipe.

What Can You Use Instead of Oak Galls?

There are 1,300 species of gall wasps across the world, and they parasitize all kinds of different trees, not just oak trees. These trees includes citrus, hickory, maple, beech, chestnut, and coral. You can use any of these galls to make ink. You can also use acorns, lamp black, and some berries. Potentially, anything with a high level of tannins or tannic acid will work in an ink recipe, but you’d need to experiment or look at historic recipes to find the right quantities and blends of ingredients.

History of Oak Gall Ink

It’s fascinating to think that oak gall ink has been used since Ancient Rome and maybe before. The earliest record of actual iron gall ink is early in the 4th century, and experts believe it was probably in use long before then, too. It’s been used to create everything from ancient medial texts and monastic scrolls to the Declaration of Independence. It’s really amazing to think that these deformities from oak trees were central in creating some of the world’s most important documents.

While those early makers and users of iron gall ink knew that these simple ingredients could be combined to make lasting ink, they didn’t have the knowledge of the chemical reaction that occurred to create the ink. Making iron gall ink is easy, making good quality ink isn’t as easy – or at least it wouldn’t have been easy without a lot of experimentation, as a poorly made gall ink can actually be corrosive and eat its way right through the vellum, parchment, or paper it’s used on. For this reason, the recipe I use is based on the first known reliable and stable oak gall ink recipe from the 1660s.

How to Make Oak Gall Ink

Before you start making your own ink, remember that this recipe behaves exactly like liquid acrylic or other modern inks, so it will stain everything it touches and you’ll struggle to wash it out. So, be smart. Use old utensils and bowls that you don’t mind getting stained. Wear old clothes and wear disposable gloves. And make the ink in the kitchen, with old rags or newspaper laid down to catch any spills. Whenever I’ve made this recipe, I’ve actually done it outside in my little workshop.

Harvesting Oak Galls

In fall, when the juvenile parasitic wasps have emerged from their galls, it’s time to harvest them. You’ll know if the wasp has vacated the gall because there’ll be at least one comparatively large hole in the gall, usually at the bottom. Cut the galls from the tree gently, avoiding harming the tree branches. Once fall is well underway, you may also find them littered on the ground beneath the tree.

One important thing to note: Drought-stressed trees are more prone to attack from gall wasps than well-watered, healthy trees. So in a dry year, when the galls are abundant, if you like making the ink, harvest enough galls to last you for a few years. Remember that it only takes about a dozen galls to make a good-size bottle of ink.

Drying Oak Galls

Once you’ve harvested the empty oak apples, you’ve got to dry them. There are several options for how to dry oak galls. You can pop them in an oven set on a very low heat for a few hours or leave them in a dry, sunny spot in the house for a few weeks. But the easiest and most effective way to dry oak galls is to dehydrate them. I put mine in my Excalibur and set it to about 100 F (65 C) and let it dry them out for 12 to 24 hours, depending on how fresh or dry they were when I harvested them.

You want the galls as dry as possible. This is particularly important if you want to store them for later use. If there’s still moisture left, the galls will grow mold or otherwise spoil and be useless.

Crushing Oak Apples

Your harvested oak wasp galls are nice and dry at this point, so now you need to crush them. Be warned – when thoroughly dry, oak apples are hard and tough and can take some serious elbow grease to crush up. The easiest wat is to use a heavy mortar and pestle. I use a big stone one like this.

For this particular recipe, you’ll need 2 ounces of crushed oak galls.

Soaking Oak Galls

Once they’re dry and suitably crushed and you’re ready to make your ink, you have to soak the oak apples. If you’re going for 2 ounces of crushed galls, then add 1 pint of water. Soak them for 24 hours then strain through a cheesecloth. I use an old cheesecloth, like this one, that I reserve for anything not-edible, just to be on the safe side.

Adding Ferrous Sulphate to oak gall ink

Ferrous sulphate is not a term you’ll see in most historic recipes for oak galls ink, as it was formerly known as vitriol or copperas. This ingredient is the produce of iron that’s been passed through sulphuric acid. The end result is ferrous sulphate – a green crystallised substance. You need to add one ounce of ferrous sulphate to the water from the oak galls.

In some recipes, before the discovery of and wide availability of ferrous sulphate, many recipes called for scrap iron or iron nails instead of a precise measure of ferrous sulphate. The problem with this approach, of course, is that it’s impossible to accurately measure the amount of iron you’re adding to the recipe, which is why I’ve chosen to use this ferrous sulphate.

However, I’ve also seen people use a rusty iron pot to soak or boil their oak galls and need to add no other iron products to get usable ink. Others prefer the traditional method of using scrap iron or iron nails and vinegar while others prefer to use wire wool and vinegar. There are lots of variations – and I’d happily use any of them in a pinch. But when I can get ferrous sulphate, it makes more sense to use it so that I can get a reliable result every time.

As soon as you add the ferrous sulphate to the oak gall solution, it reacts with the tannic and Gallic acids from the galls and turns black. You’ll also notice your ink become thicker.

Adding Gum Arabic to oak gall ink

Gum Arabic is something you’re probably familiar with if you dabble in painting or other art forms, as it’s commonly used as a binder, particularly in watercolours and gouache. Gum Arabic is the sap from the gum acacia tree that’s been dried and, when used in iron gall ink, improves colour, brilliance, and stability. It also adds substance, binding the solution together and improving flow and coverage. Add half an ounce of gum Arabic to the ink and stir vigorously. I use this one which works really well.

Using Oak Gall Ink

Because oak gall ink can be corrosive, I prefer not to put it in my regular fountain or cartridge pens. Instead, I use the ink with glass dip pens, quill pens (tutorial on making quill pens coming soon!), or bamboo pens like these ones.

The inclusion of the Gum Arabic improves the flow and increases surface tension, making the ink perfect for dip pens, as the ink goes further with each dip, and the pen draws the ink across the paper smoothly.

One thing that I found super interesting the first few times I used this ink is that when you first write with it, unlike commercial ink, it’s pale – almost translucent. The first batch I made was a bluish color at first and the second batch was an earthier brown-gray. However, as the oak gall ink reacts with the oxygen in the air, it darkens as it dries to black or almost-black.

Parasitic gall wasps were so important for medieval scribes because they inject their eggs into the leaves of oaks, walnuts, and other trees, causing the tree to produce galls that were dried out and used to make iron gall ink

This particular recipe for iron gall ink flows beautifully. The addition of the Gum Arabic increases the surface tension and binds the ink, creating a smooth-flowing ink that transfers from pen to paper effortlessly. It’s great for everyday writing, for calligraphy, and for drawing.

The Magna Carta, the American Declaration of Independence, and Jane Austin’s Pride and Prejudice were all written with iron gall ink. As were many other important texts since Ancient Rome.

Yes, in certain conditions, iron gall ink can fade with exposure to sunlight. However, a well-made oak gall ink will take centuries to fade, even with regular UV exposure. And mostly, it doesn’t fade completely. It turns to a pale brown and develops a kind of halo around each letter, which can make it challenging to read.

Additionally, poorly made ink that’s too acidic will eventually eat away at the paper it’s written on, rendering it illegible.

Yes, you can make ink with acorns. Like galls, acorns have a high concentration of tannic acid or tannins, so make a good substitute when galls aren’t available.

It really depends on the recipe you follow. However, whichever oak gall ink recipe you follow, be sensible and don’t eat or drink it. Avoid getting it in your mouth! Similarly, keep it sealed and away from pets and kids. Take the same precautions you would with any ink, paint, or other art material.

The best way to store oak gall ink is in a suitable ink bottle. For daily use, I like these little glass bottles with plastic caps. They’re inert, so won’t react with the ink, and short and wide enough to be stable. The mouth is also suitably wide for dipping pens or drawing up ink into an empty cartridge.

For storing larger quantities of gall ink rather than a daily use bottle, I like to use wide mouth amber glass jars with PET lids like these ones, because they’re inert and they protect against UV light, which can change the composition and condition of the ink over time.

I store the amber glass bottles full of ink in a dark, cool cupboard, and just decant it into my little everyday bottles whenever I run low.