Microsampling and Determination of Metals in Iron Gall Ink

Iron gall ink contains transition metals such as Fe, Cu, and Mn which are known to catalyze chemical reactions in support materials such as paper and parchment, which eventually leads to their deterioration over time. Identification of metals in ink can be an important step prior to the conservation treatment of a written document. In this work, syringe needles (16G–23G) were used to sample micro-cores (∼0.7 mm in diameter) of ink and paper prior to analysis. Metals were extracted from the micro-core with HNO3, prior to analysis using graphite furnace atomic absorption spectroscopy (GFAAS).