gall-nut ink (English, noun)
expansion: gall-nut ink (plural gall-nut inks)
Senses:
glosses: 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
Forms:
form: gall-nut inks
tags: plural