> One person has
> suggested the Higgins Eternal Ink. The description of that ink I read
> on one web site says that it's "suitable for pens if thinned." What
> does that mean?
Higging Eternal ink is a carbon ink, so it actually has particles in
it. Most fountain pen inks use a dye for color. I've never used a
carbon ink, so I don't know what trouble it might cause you. If you
let some dry up in your pen, it might be harder to clean than a
regular non-particulate ink.
I can't help much on choosing inks, since I've been using the same ink
(Waterman Florida Blue) for years. It's a washable ink, and I can
verify that it will wash clean off the page with water.
I have heard lots of pen people say good things about Noodler's ink,
so that would be probably be my first choice right now if I were
looking for a new ink. (When I run out of my current stash, I'll
probably pick a Noodler's.) Noodler's inks are available in a whole
rainbow of colors, and some of those inks are specially made to be
permanent. If you're worried about permanence, that may be the best
way to go.
More on Noodler's: