Posted on March 28, 2026
Tags: madeof:atoms, topic:inks

Note

This post will be updated in the next weeks with the test results as they become available.

Note

Most of the images in this post have no real alt-text: they are all scans of the test sheet at various stages through the test, and the results visible on them are described in detail at the end of the post.

Most of the time, what people write by hand will either end up inside a notebook in a drawer or cupboard where it’s well protected, or thrown in the recycling where it doesn’t matter. There are times, however, when things will be exposed to light: it doesn’t matter whether it’s a work of artistic calligraphy that you want to frame or a passive-aggressive notice left in the atrium of a building; it is useful to know whether the work will remain legible or it will fade into nothing in a short time.

A few inks are tested by the producers for lightfastness according to some established standard, a few others are declared lightfast in a generic way, but a lot come with no indication at all. Proper testing according to the standard scales requires significant equipment to precisely control the exposure, but it’s significantly easier — and fun — to do a simple test to divide the inks into three categories:

• suitable for framed calligraphy, i.e. it looks the same after 3 months of direct sun exposure;
• suitable for complaining about the way your neighbours deal with the trash, i.e. still readable after 3 months of exposure;
• not suitable for either, i.e. has faded significantly in the same time.

In the past I’ve done some such tests by taping some sheets to a south-east facing window, and I’ve noticed that most of the results were already apparent after a month, and there was basically no difference between two and three months of exposure, but spring equinox to summer solstice is a nice timeframe to use for such a test (and it leaves time for a second test of different materials from summer solstice to autumn equinox), so this is what I’ve chosen to do this year.

Rather than a window, now I have access to a south-facing covered balcony that is protected from rain but receives quite a bit of direct sun, so instead of taping sheets to the windows¹ I’ve prepared a sturdy cardboard panel that I can leave on a table on the balcony, hopefully safe from the rain, but well exposed to the sun.

And then made a quick test, and realized that without the window glass in front, the black strip used to cover the unexposed half of the sample doesn’t lay flat and lets some sun in, so I used an old cheap²glass frame instead of the panel.

The next step, already in January, was mentioning in a fountain-pen enthusiasts forum that I planned such a test, and asking if people were interested in having me buy a few samples of more inks when I was buying my next pen. The word “enthusiasts” is probably a hint of the reason why soon afterwards I received a package with the pen I had planned to buy, its converter, and a couple dozens ink samples. And then a couple envelopes with additional samples of inks that weren’t available on the shops, from said enthusiasts.

Added to the inks I already had acquired since the last lightfastness test, it meant that they couldn’t all fit in one single page, and thus I had some room to add some inks I had already tested: some were requests, and for others I tried to select ones that felt relevant. Since I’m changing the test setup, I’ve decided I should probably keep doing this until I’ve tested again all of the inks I still have available.

For the paper, I’ve used A4 sheets of Clairefontaine Dessin Croquis 160 g/m², one of my staples that I’m sure I will have available in the next years, printed with a dot pattern with a laser printer, using this pdf. And as for the pen I’ve used a fresh Brause n°361 nib: loading a fountain pen with all of these inks wouldn’t be a reasonable effort, and the 361 is one of the writing implements I use most anyway. I also used a glass pen to fill a couple of squares on the paper with more ink. One side of each sheet was then covered with a strip of 300 g/m² black paper (also from Clairefontaine), kept in place with three dots of non-permanent two sided tape, put in the frame and set out in the sun on the morning of 2026-03-20, the day of the spring equinox.

While I was filling the sheet for the lightfastness tests, I decided to also prepare a second set of sheet, for a liquid resistance drop test.

On each line, beside the name of the ink, I added five sets of crossing parallel lines, and let everything dry for a few days.

Then I used a syringe to put a drop of a liquid on each set of lines, waited for it to be absorbed into the paper and to dry, at least overnight, but sometimes also for a day or two (life happened), and then looked at the results and did the next test.

The first liquid was water, with the usual wild difference between washable and permanent inks, and all of the intermediate possibilities.

The second liquid was isopropyl alcohol, and I was surprised to see that, with very few exceptions, most inks didn’t change at all. I wonder whether that’s related to the fact that instead of forming a drop it was absorbed almost immediately into the paper, and dried in a very short time.

The third liquid was hydrogen peroxide: beside the individual results I noticed that its column yellowed visibly; I wonder whether that means that the paper I used has optical brighteners, and it will also yellow under the sun: that wouldn’t be ideal, but it would also be a surprise, for paper that is acid free and sold for arts.

The fourth liquid was citric acid, by mixing a bit less than a teaspoon of citric acid granules in just enough very warm water (heated to 70°C, i.e. the lowest temperature available on my kettle) to dissolve most of the acid. I forgot that I had some old PH strips until one hour after I’ve put the drop on the paper, and I don’t know whether something had changed, but when I did remember about them it showed a deep red between 1 and 2. I don’t think I can trust those strips too much, however.

This backfired badly: the drop of citric acid never dried out, but formed a sticky paste that prevented me from scanning the results, and I’m not sure whether I’ll do the last test, which was supposed to be household bleach.

Luckily I had scanned the partial results, and they are shown here.

After one full day with plenty of sun, nothing really had changed, except possibly for a vague hint that the Herbin Bleu Myosotis may have have been a bit lighter than it started, but it may also have been a suggestion.

After three days, however, some results started to show, with the most fugitive inks starting to be visibly changed, becoming either paler or in some case duller.

And the full week showed more of that, with a few more inks starting to show visible change.

These are the inks I’ve tested, and here I’ll add notes on the results, as soon as they will be available, keeping this section updated.

When nothing is mentioned, it means that there were no changes, either under the light or under the various liquids.
Lamy Sepia
Not resistant to water, the drop becomes an uniform colour spot.

After one week it started to be just slightly paler.
Sheaffer Skrip Red
Not resistant to water, the drop becomes an uniform colour spot.

After one week it started to be just slightly paler.
Waterman Audacious Red
Not resistant to water, the drop becomes an uniform colour spot.

After three days it started to be just slightly paler, after a week visibly so.
Waterman Harmonious Green
Not resistant to water, the drop becomes an uniform colour spot; the hydrogen peroxide drop looks a bit lighter than the one with just water.

After one week it started to be just slightly paler..
Waterman Mysterious Blue
Not resistant to water, the drop becomes an uniform colour spot; the hydrogen peroxide drop is significantly lighter and tends towards green.
Waterman Serenity Blue
Not resistant to water, the drop becomes an uniform colour spot; the hydrogen peroxide drop is almost completely bleached to a light yellow.

After one week it started to be a bit duller.
Visconti Blue
Not resistant to water, the drop becomes an uniform colour spot.

After one week it was visibly duller, looking darker than the original.
Montblanc Royal Blue
Not resistant to water, the drop becomes an uniform colour spot; the hydrogen peroxide drop is almost completely bleached to a light yellow.

After one week it started to be just slightly duller..
Montblanc Mystery Black
Not resistant to water, the drop becomes an uniform colour spot.
Aurora Nero
Not resistant to water, the drop becomes an uniform colour spot.
Online Duft Blueberry
Not resistant to water, the drop looks very washed out, although a hint of the original shape can be guessed; the hydrogen peroxide drop is almost completely bleached to a light yellow.

After one week it was visibly paler and duller.
Diamine Forever Ink - Smoky Mauve
.
Diamine Forever Ink - Honey Pot
.
Diamine Forever Ink - Coral Blaze
.
Diamine Forever Ink - Red Ochre
.
Diamine Graphite
Not resistant to water, the drop becomes an uniform colour spot.
Diamine Rustic Brown
Not resistant to water, the drop becomes an uniform colour spot.
Diamine China Blue
Not resistant to water, the drop becomes an uniform colour spot; the hydrogen peroxide drop is almost completely bleached to a light yellow.
Diamine Inkvent Purple Edition - Glacier
Not resistant to water, there is a drop of uniform colour, but it maintains a somewhat recognisable shade of the original shape.
Fountainfeder STEVE
Not resistant to water, there is a drop of uniform colour, but it maintains a somewhat recognisable shade of the original shape.
Pilot Iroshizuku Syo Ro
Not resistant to water, there is a drop of uniform colour, but it maintains a somewhat recognisable shade of the original shape.
Pilot Iroshizuku Shin-Kai
Not resistant to water, there is a drop of uniform colour, but it maintains a somewhat recognisable shade of the original shape.
Rohrer & Klingner IG Ebony
Not resistant to water, there is a drop of uniform colour, but it maintains a recognisable shade of the original shape; under hydrogen peroxide the shade is significantly lighter.
KWZ IG Orange
Not resistant to water, the drop becomes an uniform colour spot; the hydrogen peroxide drop is significantly bleached to a light orange.
Kallipos.de Schwarze Eisengallus-Tinte
Water stains the paper, leaving however the original shape quite visible; is it almost completely bleached by hydrogen peroxide.
Kallipos.de Blaue Eisengallus-Tinte
Water stains the paper, leaving however the original shape quite visible; is it almost completely bleached by hydrogen peroxide.
Rohrer & Klingner IG Salix
Water stains the paper, leaving however the original shape quite visible; is it almost completely bleached by hydrogen peroxide.
Rohrer & Klingner IG Scabiosa
Water stains the paper with a significant purple spot, leaving however the original shape quite visible; is is a bit bleached by hydrogen peroxide, but still quite readable.
Pelikan Edelstein Tanzanite
Not resistant to water, the drop becomes an uniform colour spot, but there is a visible trace of the original shape.
Montblanc Burgundy Red
Not resistant to water, the drop becomes an uniform colour spot, with just a hint of the original shape; slightly bleached by hydrogen peroxide.
Cifra inchiostro finissimo verde alla lavanda
Not resistant to water, the drop becomes an uniform colour spot; quite bleached to a light yellowish green by hydrogen peroxide.

After one week it was visibly paler.
Sennelier Abstract acrylic ink 917 purple
.
The Feather Pen Ink
.
Eloquentia Inchiostro nero
.
DeAtramentis Document Blue
.
DeAtramentis Document BlueGrey
.
DeAtramentis Document Brown
.
DeAtramentis Document Fuchsia
.
DeAtramentis Document Grau
.
DeAtramentis Document Green Grey
.
DeAtramentis Document Light Grey
.
DeAtramentis Document Moosgrün
.
DeAtramentis Document Orange
.
DeAtramentis Document Purpurviolett
.
DeAtramentis Document Urban Sienna
.
KWZ Sheen Machine
Not resistant to water, the drop becomes an uniform colour spot; the hydrogen peroxide bleached away the red sheen. This was one of the only two inks to react to isopropyl alcohol, which caused a pale cyan halo around the lines.

After three days it was still perfectly readable, but had visibly lost some red sheen, after one week the red had completely gone and it looked very dark blue (but still shiny)
KWZ Walk over Vistula
Not resistant to water, the drop becomes an uniform colour spot.
KWZ Warsaw Dreaming
Not resistant to water, the drop becomes an uniform colour spot.
Octopus Neon Violett
Water very lightly stains the paper, leaving however the original shape quite visible. The other ink that reacted to isopropyl alcohol, with a pale purple halo around the lines.
Octopus Write & Draw Elephant Black
.
Platinum blue black
Water stains the paper, leaving however the original shape quite visible; it is significantly bleached by hydrogen peroxide.
Pelikan 4001 Brillant-Schwarz
Not resistant to water, the drop becomes an uniform colour spot.
Pelikan 4001 Blau-Schwarz
Water stains the paper, leaving however the original shape quite visible; it is significantly bleached by hydrogen peroxide.
Pelikan 4001 Königsblau
Not resistant to water, the drop becomes an uniform colour spot, with just a hint of the original shape; significantly bleached by hydrogen peroxide.

After three days it had started to be slightly paler.
Herbin Bleu Myosotis
Not resistant to water, the drop becomes an uniform pink spot, significantly bleached by hydrogen peroxide.

After three days it was already visibly paler, after one week it was a pale grey.
Faber Castell Royal Blue
Not resistant to water, the drop becomes an uniform colour spot, with just a hint of the original shape; significantly bleached by hydrogen peroxide.

After three days it was slightly duller.
Koh-I-Noor Fountain pen ink blue
Not resistant to water, the drop becomes an uniform colour spot, with just a hint of the original shape; significantly bleached by hydrogen peroxide.

After three days it had started to be slightly paler, more so after one week when it had also turned grey.
Koh-I-Noor Document Ink Blue
.
Koh-I-Noor Document Ink Black
Water leaves a very light stain, but the original shape doesn’t look changed.
DeAtramentis Document Black
.
Waterman Intense Black
Not resistant to water, the drop becomes an uniform colour spot, with a trace of the original shape still visible; very lightly bleached by hydrogen peroxide.
Herbin Perle Noir
Not resistant to water, the drop becomes an uniform colour spot, with a trace of the original shape still visible.
Parker Quink black
Not resistant to water, the drop becomes an uniform colour spot.
Platinum Carbon black
.
Rohrer & Klingner Documentus Black
.
Sailor Pigment Kiwaguro
.
Platinum Dyestuff Red
Not resistant to water, the drop becomes an uniform colour spot; very lightly bleached by hydrogen peroxide.
Noodler’s Eternal Polar Blue
.

1. which would be spend the day covered by mostly closed shutters anyway, because they receive quite a bit of direct sun, and we don’t want that to enter the house during the summer.↩︎
2. and thus, I hope, not especially UV-filtering.↩︎

blog.trueelena.org/blog/2026/0…