The grandchildren and I have picked damsons from the hedgerows and the garden. Most of them will be made into jam, but I am making ink from some of them. It is not something which I have done before, so I am following instructions from books and web sites. So far I have extracted clear juice and added vinegar and salt. I must admit that my measurements for the salt and vinegar are guess work, so I might end up with an odd concoction. The other berries such as elder, blackberries and sloes should also produce some kind of pigment. How effective they are as inks depends of course on how light fast and durable they are, so lots of tests will follow.