KWZ is a relatively new boutique ink brand from Poland with is available from Vanness Pens in the US. You can find out more about them at their website. Actually, I use “them” & “their” out of habit, the ink is made by one guy. I bought three bottles of KWZ ink at the Washington DC Pen Show including KWZ Gummiberry.
My introduction to the KWZ brand was back in June with KWZ Iron Gall (IG) Blue-Black and wasn’t very impressed with that ink. It was fine but nothing special in my opinion. KWZ got it’s initial buzz from its variety of iron gall ink colors. There is a IG Gummiberry but this one is a non-IG ink. (I do have a bottle of the IG version, but I’ve yet to open the bottle.)
I have two bottles of non-IG KWZ inks (Green #2 is the other) and both have the same odor. I don’t consider the odor either good or bad, it’s just there and it’s strong when the bottle is opened. It does smell like a chemical. It dissipates a bit when it’s in the pen and I haven’t noticed it with inked pens. My KWZ iron gall inks don’t have the same odor.
I really liked the color right from the beginning. It looked great in the medium Sailor KOP nib as well as the thinner Visconti Homo Sapien EF nib. There was some slight line variation with the wider nib that wasn’t there with the thinner nib. Still, even with the extra fine nib the line was clearly visible and the color was vibrant. I don’t have a lot of purple inks to compare this to and it’s been awhile since I inked up one of the ones I have.
The line is true to the nib size and I haven’t encountered any noticeable feathering. There is some heavy show-through and I did encounter some minor bleed-through. While writing on my Doane Paper writing pad, with the extra fine nib, I noticed a few dots each time I went to a new page. A little research showed these were under places where I had crossed out or written over something, so there was extra ink there.
As the water test shows, the ink has no water fastness worth noting, so it’s not a surprise that the ink was easy to clean from my pens. The Sailor KOP and Lamy AL-Star are cartridge/converter pens which are generally easy to clean. So they were quick and easy as expected. The Visconti Homo Sapien is a power filler (similar to a vac filler) so it generally takes longer to flush. The Gummiberry was flushed from the pen well before the tedium set in.
The KWZ Gummiberry quickly became one of my current favorite fountain pen inks and has been in pen since I got it. Much of this may be because the color is relatively unique for me, but the friendly ink properties also contribute a lot. The only potential downside is the odor, which doesn’t bother me. Bleed or show-through may bother some people but it’s not bad with my pens and paper of choice, at least not bad enough to bother me.