It can be purchased through archival and conservation supply stores, such as Conservation Resources or Conservation Supplies Australia . If you'd like, I can: Provide instructions on how to use the test paper
It is used by conservators to test manuscripts and documents without damaging them because it is non-bleeding. Gall-10rar
Explain how to once it is detected Suggest storage methods to prevent further degradation Let me know what you'd like to explore further. Iron Gall Ink Test Paper - Conservation Supplies Australia It can be purchased through archival and conservation
The test paper is moistened and applied to the ink. If iron (II) ions are present, the test paper changes color (turns a red/purple complex) due to the indicator bathophenanthroline reacting with the iron. Gall-10rar