The De Atramentis Archival ink is the best waterproof permanent ink currently available on the Greek market. I use it for drawing and painting, but it is also perfect for writing. I believe it can be used for manuscripts that no one wants to fade away. It dries quite quickly, and I can immediately go over it with a wet brush using watercolors. Deep black, it has good flow in the nib, and it hasn't clogged even after months of use and infrequent cleaning. (Of course, since it is pigmented ink, it requires a bit more effort in terms of light scrubbing to remove the blackness from the surfaces of the nib or the converter if it shows in a demonstrator).

Ideal for use with a dip pen as well.

Serious product, inexpensive for its quality and durability.