Can I mix different fountain pen inks?

Although mixing inks to create custom colors might seem appealing, it is generally not recommended. Fountain pen inks are formulated with specific solvent and dye balances to ensure proper flow and drying characteristics. Mixing inks can lead to unpredictable chemical reactions or a change in viscosity, and in some cases may cause insoluble particles or precipitates to form. These can clog the intricate feed of your pen or reduce the quality of your writing. If you’re determined to experiment, always mix in a separate container with only small quantities and test the resulting mixture on paper before filling your pen. Even then, be prepared for a performance that might differ from that of the original formulations