Diamine is a British based company that has been manufacturing ink for fountain pens since 1864. Using traditional methods and ink formulas, Diamine fountain pen ink is now regarded worldwide as one of the finest inks available, and unlike many other brands it is made right here in the UK. Diamine ink is a water based which makes it suitable for use in any fountain pen that has an ink converter fitted for using bottled ink. There are over 100 different vibrant colours to choose from. The ink is particularly well known for its free flowing properties and for not blocking or clogging up your fountain pens feed or nib. From time to time Diamine bring out special editions of their ink such as the 150th anniversary ink. They have also recently released their unique shimmering fountain pen ink which will really make your writing sparkle. Also available are Diamine ink cartridges with a choice of over 20 different colours, these are international standard size cartridges and will fit all fountain pens that take this size of cartridge.