Nemosine Fission Classic Blue 0.6mm Fine Stub Fountain Pen: A Review

(Susan M. Pigott is a fountain pen collector, pen and paperholic, photographer, and professor. You can find more from Susan on her blog Scribalishess.)

Nemosine produces a variety of reasonably-priced fountain pens in three series: the Singularity, the Neutrino, and the Fission. The Fission is named after “the process by which a nucleus splits into smaller particles through a nuclear reaction or radioactive decay, releasing large amounts of energy. Nuclear binding energy is the energy required to dismantle a nucleus into its component protons and neutrons” (quoted from the Nemosine site).

The Nemosine Fission comes in four colors: classic blue (the one I’m reviewing), gunmetal, ice, and navy, and you can get them with nibs in EF, F, M, B, and 0.6 stub.

The Fission is an all-metal fountain pen with a stainless steel nib. The body of the pen is coated in lacquer and has what I assume are stainless steel accents. The pen comes with several black ink cartridges or you can use the included converter.

My pen is a beautiful Robin’s egg blue color. The silver accents complement the blue perfectly. The clip is engraved with an “N” and it’s nice and tight.

The body is decorated with two silver rings (one at the bottom of the cap and one at the top of the barrel) and silver threads at the bottom of the barrel that allow you to post the cap by screwing it on.

This is a hefty pen, weighing 43 grams without ink (though ink adds negligable weight). The pen is medium sized: 5.0 inches uncapped, 5.5 inches capped, and a little over 6.5 inches posted. As stated above, to post the cap you actually screw it on, so it posts very securely.

As with all pens with metal grips, the Fission’s grip, while smooth, can become slippery if you’re fingers sweat. I’d prefer having some sort of engraved pattern to help steady my fingers.

The stainless steel fine stub nib is decorated with scrollwork, an “N” for Nemosine, and the size of the nib. It’s a relatively smooth nib and is very hard—no bounce or softness at all.

I found ink flow to be unreliable. The pen would write well for a while, then the ink flow would start to dry up. I had to manually force ink down into the feed by turning the converter. The flow randomly fluctuates between wet and dry.

I’m going to rinse out the pen, floss the nib, and try again. Fortunately, Nemosine has a generous three-year guarantee that allows you to send the pen in for a replacement for any reason. You simply pay $5.00 to cover testing, labor, and return postage. I’ll definitely take them up on that if the writing doesn’t improve.

Regardless, I like the 0.6mm fine stub nib. It offers a little bit of line variation, and when the ink is flowing well, it writes beautifully.

You can purchase the Nemosine Fission from JetPens for $29.99.


  • The Nemosine Fission is a rock solid pen—hefty, well-manufactured, and beautiful.
  • For those who like posting caps, the Fission’s screw-on system is reliable.
  • The steel nib is smooth. I especially like the variety of nib sizes Nemosine offers. The 0.6 stub is a choice many writers will enjoy since it’s not too broad but offers some line variation.
  • The pen comes with a generous three-year guarantee.


  • This is a heavy pen, so writers whose hands cramp when using heavy pens will want to look elsewhere.
  • The metal grip is slippery, especially if you get sweaty fingers like me.
  • The ink flow on my pen was unreliable, ranging from super wet to super dry. I’m hoping this is something that will work itself out with some thorough cleaning and flossing the nib. If not, I’ll make use of Nemosine’s guarantee.

(JetPens provided this product at no charge to The Pen Addict for review purposes.)

Posted on June 30, 2017 and filed under Nemosine, Fountain Pens, Pen Reviews.