We discussed about the tools to write calligraphy with and we also thought on a variety of tools from there.But we need a medium to write with and that is ink.In calligraphy, India Ink is always best or Sumi Ink. There are inks available in the market labelled "Calligraphy Ink" they are similar to these inks, that's good .But if that is not available, theses options would work just the same .
Never write any piece of good calligraphy with simple water-based fountain pen ink as they are light and are very thin compared to the above said inks that are used.But you should use on this simple water-based ink when writing with a fountain pen, if you use the thick ink, you may clog and ruin your fountain pen. These inks are used in dip pens of any kind. Higgins , Manuscript,Cretacolor, Speedball and many other companies manufacture inks that are best for calligraphy.You can prepare your own ink also.
If you are trying to write in different colours of ink , you might look for inks of colour or you can go with gouache of ink consistency or acrylic paints of the same consistency.
If you are doing pointed nib calligraphy, you might want to add some gum arabic or some glycerin to improve the elasticity of the ink . That will help in doing the calligraphy smoothly.Do not put alot , but a little will do the work fine, else the ink will not be usable . Do not use this ink ( with glycerin) for other broad nib calligraphy, you will not get good letters with it.
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