Iron gall ink is one of the oldest writing inks in existence, with a history stretching back over a thousand years. Used by Leonardo da Vinci, Johann Sebastian Bach, and countless other historical figures, iron gall ink has a unique character that modern dye-based inks cannot replicate. Here is everything you need to know.
What is Iron Gall Ink?
Iron gall ink is made from a reaction between iron salts (usually iron sulphate) and tannic acid derived from oak galls, the small growths that form on oak trees when wasps lay their eggs inside. When the two components combine, they produce a dark, permanent ink that bonds chemically with paper fibres rather than simply sitting on the surface.
This chemical bonding is what makes iron gall ink so permanent and archival. Documents written in iron gall ink have survived for centuries, which is why it was the ink of choice for legal documents, manuscripts, and official records throughout history.
How Does Iron Gall Ink Look?
Iron gall inks typically start out as a blue-grey or greenish colour when first applied, then darken to a deep black or dark brown as they oxidise and dry. This colour shift is one of the distinctive characteristics of iron gall ink. Many modern iron gall formulations are adjusted to start darker, but the oxidation effect is still present.
Iron gall inks also tend to show excellent shading, with lighter and darker areas depending on how much ink is deposited. This makes them particularly beautiful for expressive handwriting.
The Pros of Iron Gall Ink
- Permanence: Iron gall ink is highly water-resistant once dry and extremely archival. Ideal for documents, journals, and anything you want to last.
- Shading: Excellent shading characteristics that reward good writing technique.
- Character: A unique, historical quality that no modern dye ink can replicate.
- Lubrication: Many iron gall inks write with a slightly dry, crisp feel that some writers prefer.
The Cons of Iron Gall Ink
- Corrosive: The acidic nature of iron gall ink means it can corrode metal pen components, particularly steel nibs and feeds, if left in the pen for extended periods.
- Requires more maintenance: Iron gall pens should be cleaned more frequently than pens used with standard inks, ideally every two to four weeks.
- Not suitable for all pens: Avoid using iron gall ink in vintage pens with rubber sacs or in pens with steel nibs that are not designed for it. Gold nibs and modern steel nibs from reputable brands are generally fine with regular cleaning.
- Can stain: Iron gall ink can stain pen barrels and feeds if left to dry.
Best Practices for Using Iron Gall Ink
- Clean your pen every two to four weeks, even if you are still using the same ink.
- Never leave iron gall ink in a pen for more than a month without cleaning.
- Always clean thoroughly before storing a pen used with iron gall ink. See our fountain pen cleaning guide.
- Use a pen with a gold nib or a modern steel nib from a reputable brand.
- Avoid using iron gall ink in vintage pens unless you are experienced with their maintenance.
Our Iron Gall Ink Recommendations
We stock iron gall inks from several trusted brands:
- Rohrer and Klingner - the historic German ink maker produces some of the finest iron gall inks available, including their Salix and Scabiosa formulations.
- KWZ - the Polish ink maker produces excellent iron gall inks with beautiful colours and good flow.
- Diamine - Diamine's Registrar's Ink is a classic iron gall formulation that is reliable and well-behaved.
- J. Herbin - the historic French ink maker produces a traditional iron gall ink with excellent archival properties.
Is Iron Gall Ink Right for You?
If you value permanence, archival quality, and the unique character of a historical ink, iron gall is worth exploring. Just be prepared to clean your pen more regularly and to use it in a pen that can handle the slightly corrosive nature of the ink. If you are new to fountain pens, we recommend starting with a standard dye-based ink and moving to iron gall once you are comfortable with pen maintenance.
If you have any questions about iron gall inks or which pen to use them in, get in touch and we will be happy to advise.