Indian ink was invented by the Chinese (who later traded it to India) while the Europeans were still playing with rocks in the neolithic age.
The ink’s black colour comes from lampblack, traditionally made from the fine, sooty residue from oil lamps. It’s essentially a non-crystalline (“amorphous”) form of the element carbon, and is also used in “carbon” drawing sticks and pencils such as Wolff’s. It is noticeably blacker than graphite or charcoal. This is because graphite’s crystalline structure reflects light, and charcoal contains impurities that can be traced to the incomplete combustion of the wood.
Lampblack is an insoluble pigment that forms a fine suspension in water. This is why it is often recommended to shake the bottle before opening. Adding a binder such as shellac or gelatin helps to stabilise the suspension, which is probably why it doesn’t seem to matter very much if you forget to shake the bottle! Classic Indian ink is made using shellac dissolved in alcohol, which gives the dry ink an attractive sheen.
Indian ink often considered to be the blackest and most permanent ink that you could wish for. It won’t fade in the sun and, once it has dried, it won’t wash off the page (so you can use it for pen and wash). It doesn’t change colour when it’s diluted.
It’s a great ink if you are happy to use a dip pen, or a brush, or a twig, or even your fingers, to apply it with. But it doesn’t play nicely with (most) fountain pens.
I’ll explain why in my next post.