Iron Gall Ink Test Paper

The Iron gall ink, made from iron salts, can alter paper in many ways: Brown discoloration on the verso of the inked areas, yellowish halos spreading out from the inked area or the inked areas becoming so weak and brittle that they crack, crumble and fall out.

Therefore in some cases being able to identify an ink containing iron is critical to make a relevant diagnosis before a restoration-preservation procedure. Slightly humidify the test paper with distilled water and apply it to the area to test, the test paper in contact with the tested area takes a red- fuchsia color if iron is contained in the ink.

• Cut out the test paper.
• Humidify the test paper.
• Eliminate the water in excess.
• Put the test paper in contact with area to test.
• Positive test.