🇬🇧 en pt 🇵🇹

gall-nut ink noun

  • acid blue-to-black ink, blue or purple when fresh, but turning intense black from iron oxidation, containing iron ions and tannic acids obtained from crushed gall-nuts and a solution of gum, or glue, and copperas, slowly replaced carbon ink and used from late antiquity to 20th century
 tinta ferrogálica, tinta metalogálica
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