I made my own walnut ink / J'ai fait ma propre brou de noix!

Calligraphy with home-made walnut ink

Walnut ink is  a liquid derived from the husk of walnuts, with staining properties.  It has been used by visual artists as a drawing and lettering medium. Walnut ink is made from natural pigment that develops when the husk- the external  fleshy envelope of the walnut starts rotting, turning from lime green when it is attached to the tree to dark brown after it has fallen off. Calligraphers like it as a lettering medium; its sepia tone creates softer effects than black ink  and can be used for washes. I was puzzled to hear that sometimes what can be referred to as walnut ink may actually be  peat-based. 

I have been curious to learn how ‘real walnut ink’  can be made,  true to its name. And maybe, I could make my own;  I noticed the availability of walnuts with their husk  at the Ottawa Farmer’s market during the month of August.   

Fresh walnuts with their husks at varying degree of decomposition

With the help of Youtube videos I found out that the process of pigment extraction can be fairly simple. In a nutshell (pun intended!), one can soak a given weight of black husks in  a given volume of water (initially very hot)  and let it sit for 2-4 days. After straining, you have walnut ink.  Another method consists of  boiling the entire walnuts with their husk for a while, and let the liquid reduce until the desired tint is obtained.  I tried both and  got very similar results.

Walnuts with black husks 

Black husks peeled from walnuts

I purchased a mix of green and blackened husked walnuts  and let them all become black on a window sill for several days (Do not leave it too long piled up as cute little green worms start wiggling in the husk flesh…).  Then I  peeled  the husk from enough walnuts to yield about 1 ounce of it. I placed it in a stocking  and tied it with an elastic band, dropped it in a glass jar and covered it with about ½ cup of steaming hot water (I used rainwater, but some suggest using distilled water).  I let it sit for 4 days.  

I then took out the pouch of husks and squeezed it in the jar to extract the concentrated pigment.  I strained the liquid again through a cheese cloth and voilà- my own walnut ink!  This is messy so wear protective wear (gloves, etc and protect your working surfaces against staining. 

Some suggest adding a drop of bleach to prevent mould growth.  I tried it on a small quantity of ink, thinking it might weaken the pigment, but it did not seem to.  Other suggested adding a bit of  gum arabic to improve smoothness of the fluid.

Pulling out the pouch of husks

Ahhh.. squeezing out the 'sepia gold'

Et voilà!

Another method: boiling the whole nuts
and reducing the liquid

I also used the other method of boiling the entire walnuts  until the reduction reaches the tint desired.  That is more work, as one needs to use dedicated coockery for that, and supervision while it is on the cooktop.   I did not see a difference in the resulting walnut inks.

It is a special feeling to do calligraphy with your own walnut ink!   If you do not have access to walnut husks, calligraphy equipment supplier like John Neal in the US sells a kit that includes the husks in a pouch, instructions, and a link to a Youtube video.