From Medieval Reconstructivism:
Oak Gall Ink Recipe
By Karen Gorst
One of the most commonly used inks in the Medieval period was oak gall ink, so named for the oak galls which serve as the basis of the ink.
Oak galls are rich in tannin and gallic acid. The tannin and gallic acid, when combined with ferrous sulfate, creates the blackness of the ink.
3 parts* ground oak galls (start with about 3-4 oz. oak galls)
2 parts ferrous sulfate
1 part powdered gum arabic
Rinsed egg shells
Distilled water (today’s answer to fresh rain water)
* Note that these are parts per volume.
Boil 12 parts distilled water. Add 3 parts ground oak galls. After 15 minutes, add the ferrous sulphate. Pour through a filter. Separately, add a small portion of the liquid to the gum arabic. Make sure the gum arabic dissolves completely. Add this to remaining liquid. Place in Bottle for storage until used. Add egg shells to neutralize the pH of the ink.
The quality and permanence of the ink is dependent upon the quality of materials used. The best ink will be produced with oak galls which are found with the wasp still inside of them. This insures that they are rich in tannin. if the eggs have hatched, a small hole will be evident where the hatched wasp made its way to freedom. Oak galls harvested in fall have a lower acid content.
Oak gall ink takes time to reach its optimum state. Over the course of six months, this ink will gradually darken. it continues to darken after applied to vellum or paper, and may appear faint when first applied.
After this period of time, the sediments will settle to the bottom of the jar. Stirring ink frequently will keep the sediments from settling. Another method of keeping sediments combined is to add urine to the ink. While this method of keeping the sediments is effective in keeping the ink of one consistency, the urine adds extra acids which must be neutralized in order to keep the parchment from deteriorating.
white pebble 