Jim P. on Nostr: Evaporation is usually the cause in my experience. It can lead to some interesting ...

Evaporation is usually the cause in my experience. It can lead to some interesting shades of the original ink, but usually it's a bad sign.

If that is happening, your pen isn't sealing very well so you might want to look at that, too, if possible. Maybe the cap isn't tightened all the way, or maybe the cap is left off the pen for prolonged times.

If it happens a lot then all of the water in the ink chamber could evaporate leaving you with a concentrated mess to clean.