I love the color blue in all its varieties. Blueberries and black beans can make nice blue inks and dyes but are fugitive and the color fades when in the light for a long period of time. I have read about the indigo plant and I plan to try making ink from the dry pigment.
Since I adore the aqua color of patinas I found a recipe and decided to try making copper oxide ink. The recipe seemed fairly easy: take some copper scraps put them in a jar with white vinegar and salt, leave it standing without a lid and soon you will see color brewing. Stir the mixture every few days, test the color until you get what you want. Easy peasy right?
Not quite as easy as I had hoped. It took many failed batches and 2 months to figure it out.
The first batch sat for 3 weeks, I kept adding vinegar but nothing happened. I thought the pennies I used weren’t 100% copper so I went and picked up a few small copper pieces at the hardware store. Still nothing. Then I tried switching the salt, again, nothing. Then I thought the vinegar might be old and wasn’t strong enough, so I switched that. Nothing.
Then it dawned on me; I had to use “iodized” salt! I live with a chef and although we have many types of salt i.e. Himalayan pink, kosher salt, sea salt, black salt even maldin salt! You won’t find regular old Morton’s iodized salt in our cupboard.
I made up a new batch and used the iodized salt. It finally worked and it is a wonderful thing to watch. The colors are astounding and get more beautiful everyday. I plan to keep a jar brewing all the time.