Diamine Registrar's

[Brilliant Bill]

Apparently this ink has a liquid shelf life that's less than what it has when applied to paper. This is around five years old, and it has precipitated out of solution. Shaking vigorously doesn't help much, as you can see in the two swabs...
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By the way, this is not one of the inks I have on sale!!

[Yazeh]

Yep that's the downfall of real IG inks. My Gutenbering Urkundentinten brown black arrived expired. The seller sent me another bottle it was more or less the same. Now I use it only for art work. However, I've used an expired Essri in a disposable pen, and it worked quite fine. It was just like a bluish ink and was quite water resistant

[Chrissy]

The "gall" ingredient is, after all, just tiny fragments of a piece of wood from a tree. After 5 years one might expect it to change.