Platinum's famous permanent waterproof ink. Platinum Carbon Ink is pigmented ink suitable for fountain pens - for documents, drawings (including line and wash) and general-purpose use. However, this ink does have the potential to damage pens if not used according to instructions. This ink can dry and clog fountain pen feeds if left too long as it contains ultra-fine carbon particles. It is only suitable for pens that are in daily use and if the pen is to be left more than a couple of days without use then we advise flushing the pen and converter.