I drew lines with about 5 years old Nahari ink on a business card and on klaf (unknown type and source of klaf). Let it air dry, then baked it in the kitchen oven at about 90 degrees C for half an hour to make sure it is really really dry.
Then, dripped water on the lines. Here is what it looks like.
On the klaf the ink spread a lot. On the card it barely spread. I then dripped more water all over the ink lines on the card. The ink for some mysterious reason did not spread. I don't know why is there such a big difference between ink on card and ink on klaf.