How does an index of Ink pH sound to you all? Here could be some pertinent information we could use:

1) Ink pH (Uniform method of determining pH needed?)
2) Date of ink purchase
3) Make/Color of Ink

Are there any ideas on how to determine ink pH? Its been a few years since I've take Chem.

Dr. Greg Clark's book, Fountain Pen Inks: A Sampler, reports pH measurements for every ink color he shows. If I correctly understand the Pen World article by him which he reprinted in the back of his Sampler, he got some of those numbers from manufacturers, measured the others himself and spot-checked a few of the manufacturers' numbers.

In that same article, he concluded (after talking with a Sheaffer representative) that most fountain pens can take most of today's inks without problems. Therefore, Dr. Clark believes that pH is an interesting fact to know, but not much of a concern.

I might hypothetically be concerned about ink pH for pens that don't have corrosion-resistant parts, for ink mixing (although another of Dr. Clark's articles in the Sampler pooh-poohs most fears about ink mixing), for mixed-media artworks (in the pre-electronic sense of "several different types of material") and for archiving.

Nevertheless, I love knowing about the pH of the inks I use!

Shall we write to Dr. Clark for permission to reprint his numbers? He might expect payment for the use of his intellectual property (from his own labor!), and the FPN is not a legal or financial entity, so that could be a problem. The FPN administrators can't even agree on whether it makes financial/tax sense to reimburse member FPN member Cam, who provides the physical hosting for us!

I posted a chart here somewhere, can't find it at present. I'll search when I'm back home and re-post if you like.
The interesting fact I remember is that WM Havanna Brown has a -ph of 7, same as water.

Gary