Oak Galls are funny little round things that can be found growing on oak tree brances. An oak gall wasp lays eggs on the branch and these galls form around the larvae. They are incredibly tannin rich and have been used in ink making since medieval times when mixed with iron.
I collect oak galls in the winter as they are easily visible in the bare tree branches. By then they have turned brown and quite tough and will need to be ground into powder with a pestle and mortar. Often they may contain a wasp so it’s good to leave your bag open and let any bugs escape.
I soaked the ground up pieces for few days in water and then boiled them for an hour. I added in small samples of different fibres; cotton, linen, silk and wool/cashmere – all without a mordant.
I simmered my fibres for an hour and left them to cool in the dye bath. During the dyeing, I had left the ground up gall pieces in with the fibres.
Next I wanted to try making ink. I strained the bath twice, through a coffee filter making sure I’d remove all the bits. I re-heated the dye and divided it into two containers; one for my ink and one for my fibres.
I added a quarter of a teaspoon of ferrous sulphate to both baths. I dipped my fibres in for 5 minutes, removed them and rinsed immeadiatly.
For my ink I added in Gum Arabic solution. It thickens up the ink and depending how much you use, you can even make it into a paste for printing. I tried a little on some watercolour paper with a paintbrush and the colour was a dark black, just as youd expect ink to be.