There are currently 30 colours in the J.Herbin fountain pen inks range and having tested the 1670 inks, you can understand my eagerness to have a crack as these. I could only source 11 vial samples in the UK so I can only judge by what’s in front of me. As writing inks go, they are a decent product, with a smooth flow and quick drying time. They all blended with water very easily and reacted with the bleach superbly, apart from the Perle Noir, there was a strong neon effect from all of them. With regards to hidden colours, there are none here, so all you creative ink geeks may be a little disappointed. On the upside, the colours are all very stable and when diluted with water behave like watercolour inks and wash out accordingly. The Bleu Azur is a little thin, in my opinion, so when used for writing may be a little too feint for legibility, but when subjected to bleach, the neon effect is amazing! These are quality inks with a heritage dating back to the 1700s. Apparently they are lightfast too – which is a real positive for artwork longevity. What’s not to like?