One day I noticed I'd like to organize my ink collection outside of my head: Make some writing samples for each color, preferably with different plens, plus a few notes how the ink performed in the pen and maybe a swab. Sorted by color so it would be easy to find a specific shade if I ever looked for one. I started out immediately using a softcover notebook.
Then I realized a notebook wouldn't be the best choice and something more modular would probably be better - so I chose index cards. Their heavier cardstock would also handle the swabs better.
I've made about 30 sample cards so far, always with the inks I'm using at the moment, and already found ink twins! Diamine Twilight and Rohrer & Klingner Verdigris look somewhat different while the ink is still wet but when dried they're hardly discernible at all. They're a nice dusky blue-green color.
|Swabs: Diamine Twilight (top) and Rohrer & Klingner Verdigris (bottom)|
Then I wrote a few lines of text, changing pens every few words. If it weren't for the fact that one pen has an italic nib and the other one a round medium I couldn't make out any difference at all.
In English it reads:
"Who can find the words written with Twilight? (Hint: It's extremely helpful not to look for color difference alone!)"
Both inks behave and flow quite well but the Rohrer & Klingner is the better deal for € 3,95/50 ml.
Do you know of any more ink twins?