As we have been conducting our ink tests, we ran into a grouping of mostly orphaned bottles that wouldn’t make for a very big story individually. So we tested them together and got them all on one page.

The ink proof sheet is on the left and the UV tested inks are on the right. Click the image above to get a better look at the ink tests.

This batch of inks was given a UV light fast test in our sunniest window from March 7, 2021, to June 7, 2021. We also tested the pH levels of the inks to see just how neutral they are. The following is all raw data that we thought you might find interesting. As we do not know the chemical composition of each ink or ink sac/converter it might go into, a pH neutral ink does not guarantee it won’t have a bad chemical reaction inside your pen. We have a professional pH tester, which we calibrated just before testing these inks. As a quick chemistry refresher, a pH of 7 is neutral like distilled water. The closer you get to 0, the more acidic the ink is. The closer you get to 14, the more alkali/base the ink is.

Surprises are the most enjoyable parts of these tests. Blues remain entirely unpredictable. One of my all-time favorite blues is Parker Penman Sapphire. Instead of fading out like most blues, it turned purple! Visconti blue fades out when thinly applied, but the thicker lines create a majestic blue-black that is even prettier than the original blue. Colorverse Quasar turned from a rich blue to a light red-purple. Omas blue did what most blues do and faded heavily. Acidity didn’t seem to effect which brands faded and didn’t. Omas was the most acidic blue at 2.3, and Colorverse was the most neutral at 7.9. Both underwent dramatic changes.

There were subtle changes in some of the inks. Visconti’s black turned a dark brown in the sunlight.

Purples fared poorly. Visconti Purple turned a pale pink. Vintage 1960s’ Waterman’s Violet almost completely disappeared. Pelikan Violet held on kinda, turning a deep reddish pink.

Waterman’s Red and Omas’ Red/Burgundy held up best. Neither seemed very effected by the sun. Also interesting was that Omas’ ink was also almost pH neutral at 7.2. We are often warned red can be the most dangerous color to put in a fountain pen. If it is pH neutral, I wonder what chemical reactions happen when it is inside a pen.

We had never previously heard of Francesco Rubinato inks before, but we loved the “Verde” green ink that was somewhere between “Shamrock Shake” and “Kelly Green.” Unfortunately, it turns into a bile-like yellow green with UV exposure.

An OLD bottle of Rotring Red was a very curious color. It was more of a brick red with a hint of orange. Was that because it was already discolored and UV exposed or was Rotring red really like that? Either way, UV didn’t effect the dry ink on the page.

The only color not yet mentioned is the Francesco Rubinato Oro (gold). This is a goupy, heavily sedimented ink filled with gold-glitter. We DO NOT recommend it for fountain pens. It is ONLY GOOD for DIP PENS. Anyhow, UV light didn’t effect it at all, and because we didn’t want to ruin our pH tester, we didn’t check its pH level, either.

Here is the table of our pH results:

Visconti Black…………………………..4.2
Visconti Blue……………………………3.9
Visconti Purple…………………………3.2
Parker Penman Sapphire…………..5.3
Francesco Rubinato Verde…………4.1
Omas Red/Burg………………………..7.2
Omas Blue……………………………….2.3
Rotring Brick Red…………………….8.5
Waterman (1960s) Violet………….3.9
Waterman Red………………………..5.9
Colorverse Quasar…………………….7.9