You see in the handwriting sample above how the ink is thicker in some places than others, thus creating a variation in saturation? This is a quality in fountain pen inks — more prominent in some than others — called “shading.” It’s a thing of great beauty, and if you’ve never reflected on it you’ve missed out on life.
(I just realized I have waxed poetic about this before! I even used the same exact words. But, so what: this is my world, you just live in it. And a rant about the beauty of fountain pen ink shading simply bears repeating. In a few months I’ll probably do it again …)
The inks that I normally gravitate towards are waterproof, fade-resistant, permanent inks, and I find that these aren’t ideal when I want shading. But thankfully the ink isn’t the only factor. A fountain pen friendly paper helps bring out the shading. And writing style matters, too: a cursive technique that has much stopping and starting works better than a steadily flowing script. Block letters work well, too.