Diamine Versus the Sun & a pH Test
People often ask what my favorite ink brand is, and, more-and-more it is Diamine. Just like the Beatles, Diamine is based out of Liverpool in the United Kingdom. However, they beat the Beatles to the scene by 100 years in 1864.
In all of my experience with the ink, so far, it has been very fountain pen friendly. Iโve had great success with it in modern and vintage pens, plus, it has a zillion different colors for sale. The only things I donโt mess with are their shimmer inks because shimmer inks clog the daylights out of pens.
Diamine blue inks generally hold up pretty well to the sunโs harsh rays. It is a rare feat among blue inks.
When I stumbled into 14 different ink bottles from a collection I knew it was time to do one of our famous inkfast tests and pH tests.
The results are interesting. Although they lose a bit of their luster, most of the blues are pretty tough and donโt let the sun and UV light bully them. Silver Fox barely fades at all. When still fresh looking, three of my favorite blues in production are Diamineโs โMajestic Blue,โ โBlue/Blackโ and โBlue Velvet.โ The only blue to really fade much was โPresidential Blue.โ
Breaking into some of the more colorful Diamine inks, the sun proves more aggressive. โAncient Copperโ holds up amazingly well, but โRed Dragonโ takes a hit. โAmazing Amethystโ really takes it hard and almost completely fades out. The very popular โOxbloodโ fairs well, but it still fades a bit.
The pH testing surprised us. As a quick reminder, in the world of pH testing a 0 is extremely acidic, 7 is neutral and 14 is extremely alkali or base. We calibrated the testing device and tested the inks at 24ยบC.
Diamine Ink Name pH Test Result
Ancient Copper 6.7
Red Dragon 2.5
Oxblood 2.5
Amazing Amethyst 6.1
Sherwood Green 4.4
Blue/Black 4.1
Oxford Blue 3.8
Presidential Blue 3.2
Majestic Blue 4.2
1864 Blue/Black 4.5
Silver Fox 4.0
Before you throw out any ink you might love, please keep in mind that the pH is only a data point. We donโt know what chemicals are in each ink, and we donโt know how their chemical properties will react to your ink sacs or converters. Weโve seen acidic inks used safely in ink sacs for years and neutral inks destroy ink sacs in a matter of months.
That said, weโve always had great success with Ancient Copper, which is one of our personal favorite ink colors.
We hope this information is interesting to youโฆand maybe even help you.
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12/08/2022
I am thrilled you did this testing. Iโm new to fountain pens, and got some ancient copper from Jet Pens. Love the color and flow, and plan to do some sketches with washes. But I became worried it wouldnโt be archival. I did a search and found your blog. Thank you! Iโm hoping my lovely baystate blue will also hold up, and will do some testing of that.