How do you make ink from blackberries?

To make ink from blackberries, start by mashing a handful of ripe blackberries in a bowl. Strain the mixture through a fine sieve or cheesecloth to extract the juice, discarding the solids. You can enhance the ink's longevity by adding a pinch of salt or a few drops of vinegar as a preservative. Finally, pour the juice into a small container, and your natural blackberry ink is ready for use!