Graf von Faber-Castell Cobalt Blue is a saturated blue color.
GvFC Cobalt Blue is part of the “Document Proof” series. It means that the ink is resistant to UV light and cannot be altered or removed from the paper without a trace. It was also designed with the standard office paper in mind. It doesn’t “feathers” on such paper and doesn’t bleeds to the other side of the page. It could be used for signing and annotating documents in the common office environment.
GvFC Cobalt Blue is suitable for all fountain pens. It has a good flow and can be cleaned out of the pen easily.
Bottled Graf von Faber-Castell inks come in the heavy glass bottles. The wide flat bottom makes them less likely to be tipped over. Each bottle contains 75ml of ink.