This German woman has been collecting the tiny balls from fountain pens for 10 years

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And now the story of - let's just call it an unusual collection. NPR's Fernando Alfonso explains.

FERNANDO ALFONSO, BYLINE: In the age of Marie Kondo ruthlessly editing one's possessions, the idea of collecting things has become quaint. But that hasn't stopped Charlotte Ruchhoft, who lives in North Germany near the Baltic Sea. She's the owner of a unique and perplexing collection - hundreds of small, tiny, purplish balls that are found in fountain pens' ink cartridges kept stuffed in an IKEA desk.

CHARLOTTE RUCHHOFT: So nowadays, I'd say that the most recent feeling that I have been feeling about this is, like, a lot of nostalgia because I remember, like, how young and how eager I was when I started this.

ALFONSO: The now 24-year-old Ruchhoft started collecting the balls 10 years ago.

RUCHHOFT: And it's like just a little constant thing, where I sit down, and I do this one thing. And I get carried away in it, but I don't get distracted. And that's kind of comforting, I guess.

ALFONSO: The collection is even more unique because these balls aren't meant to be saved or collected.

CHRIS HENLINE: We have people that collect fountain pens and collect ink, but I have not seen the little balls inside of ink cartridges. That's very interesting.

ALFONSO: That's Chris Henline. He owns a South Carolina shop that sells fountain pens. Now, at this point, you may be asking the question that a lot of social media users asked after Ruchhoft posted a picture of her collection on Reddit. Why do this? But the uniqueness is exactly what draws her to it.

RUCHHOFT: I was already kind of weird, so I just leaned into it.

ALFONSO: Ruchhoft isn't alone in her attachment to unique collectibles. Christian Braun is the founder of hobbyDB, a hobbyist web community with a half a million members.

CHRISTIAN BRAUN: I've met folks that collect sands from different beaches, lint, rubber bands and all kinds of other stuff that's not standard.

ALFONSO: And the most important thing about the sand, rubber bands and, yes, even tiny purplish balls from fountain pen cartridges - it seems for the collectors, at least - they do spark joy, which is the standard Marie Kondo applies to what to keep. Fernando Alfonso, NPR News.

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