See, nowadays if you want to indulge in a somewhat unusual hobby, there is a lot of information available out there. For example, you can learn all about black fountain ink from different manufacturers – JetPens has posted this very helpful comparison.
Differences in black ink, you say? Black is black is black, no? Well, no, not quite. (Take a look at the post.)
My favourite among them: Noodler’s Heart of Darkness, for the name, and for the blackness. I agree with JetPens – Heart of Darkness is a very black black. Although I’m not actually a huge fan of black ink. It’s a bit boring, I suppose.