gallnut ink

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Last updated

June 29, 2026

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Gallnut ink is a type of writing ink historically made from gallnuts, ferrous sulfate, and a dye. It was commonly used in medieval scriptoria. When applied with a pen, it appears black with a violet hue and darkens to a brownish-black over time. While suitable for drawing, inks with high vitriol content can degrade paper, causing the ink to show through on the reverse side. Modern chemical inks offer better stability.12

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The manufacture of gallnut ink had been known from the medieval scriptoria (copying rooms set apart for scribes in monasteries). An extract of gallnuts mixed with iron vitriol and thickened with gum-arabic solution produces a writing fluid that comes from the pen black, with a strong hint of…
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The manufacture of gallnut ink had been known from the medieval scriptoria (copying rooms set apart for scribes in monasteries). An extract of gallnuts mixed with iron vitriol and thickened with gum-arabic solution produces a writing fluid that comes from the pen black, with a strong hint of…
Read More