ou need four things, and one of them is a wasp’s nursery. Oak galls are the round growths oak trees make around a wasp egg, and they are full of tannin.

Collect a handful of galls in autumn, or buy them from a dyers’ supplier. Crush them to a coarse powder in a mortar. You want something like cracked pepper, not flour.

The four ingredients

Steep 20 g of crushed galls in 250 ml of rainwater for three days. Strain. Add 10 g of iron sulphate and watch the brown liquid turn black. Stir in 8 g of gum arabic until it dissolves, then bottle it.

Writing with it

The ink goes on a faint grey-violet and darkens as it dries. Use a dip pen or a quill, not a fountain pen: iron gall ink is acidic and will corrode the feed.

Label the bottle with the date. Good gall ink keeps for years, and it will outlast you on the page.

¶ Written by

Isolde Marr

Craft editor

Isolde trained as a manuscript conservator and still grinds her own pigments. She writes the Craft guides and tests every step in her kitchen first.

Making oak-gall ink at home

The four ingredients

Writing with it

Isolde Marr

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Walking the old salt roads

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