I was asked by someone about the relative waterfastness of several inks and figured I'd share the results.

All tests performed on Rhodia paper and washed with RO filtered water. The test with soapy water used 300ml filtered water with 20 drops of Sun Light lemon dish soap. Both were dipped in the corresponding beaker for 10 seconds then drained. They were then blotted with paper towel and air dried for 1 hour.

Dry samples:
Click to view attachment

Soapy Water/Plain Water
Click to view attachment

Nice! I'm still on the hunt for a water-resistant blue-black, and I rather like the look of the Sailor ink. Excellent test, thanks!

A very good job on your waterfastness test. I like the soapy vs. plain water distinction and your scans are just the right size to be viewed clearly in the web browser.

I am pleased at the Pelikan and Sailor Blue/Black performance. And no nib creep with those inks.

I like your testing and scans! Very well done and many thanks!

I, too, am reassured by the results for Sailor and Pelikan.

10 seconds isn't much time in the water. But I guess its representative of a quickly blotted spill.