I have always loved fountain pens, from childhood on. They're so much nicer to write with: no pressure, just slide them across the paper and leave a trail of crap writing behind. Ballpoints need pressure which eventually hurts your hand, and leave a trail of crap writing and dented paper behind.
Living in Canada, though, it was almost impossible to get decent fountain pens. At the affordable end were disposable (!) Parkers that were utter shit at every level. At the mid-range were overpriced Parkers and a few other smaller players that were utter shit, but at least weren't disposable. And at the high end you had stupidly expensive, gaudily decorated tubes that ... still wrote like shit. (Montblanc, I'm looking at you here!)
So I stopped using them.
Then I moved to China.
In China (for a variety of reasons, including one that's so funny you'd swear I was making it up if I told you so I won't) fountains are still the dominant writing instrument. Ballpoints are available and used, but most people reach for a fountain when doing anything serious. (Indeed you're NOT ALLOWED to use a ballpoint on some official documents for reasons which escape me!) As a result, I've gotten back into using fountain pens.
There's a problem, though, and that is nibs. A lot of times new pens' nibs are scratchy and hard to work with. They take some of the joy of a good fountain pen away. I had no idea how to deal with this beyond just gritting my teeth and writing with the pen until the nib is worn down to my writing position.
Then I found out I'm an idiot.
Because there's totally a way to get rid of those burrs and mis-matched tines without buying a hundred nibs and finding the ones that are perfect. It's really simple too. You get yourself one of these:
That is an ultra-fine grit Whetstone. The red side is sintered ruby and is 5000 grit. The mottled green side is jade and is 10,000 grit. A couple of minutes' work (and I mean that: about two minutes) and even the worst nib is turned into a smooth masterpiece that's a joy to write with. (It also clears up a few ink flow problems I had with one nib; not sure what the mechanism was there.)
So yes, that's ruby and jade, two gem stones, being used to fix up some cheap (by western standards) pens. 10cm×2.5cm×1cm. Meaning 12.5cm³ of ruby and 12.5cm³ of jade. As a whetstone.
Of course you pay for what you get. This little motherfucker set me back about…
…THREE FUCKING BUCKS U.S.!
What a world!
(The sintered diamond whetstone at 12,000 grit was too expensive for my tastes. At ten bucks.)