Has anyone tried mixing Aurora black with Noodlers black? I am wondering specifically about what ratio would still retain some of the bulletproof nature of the noodlers but still have the flow and lubrication of the Aurora. I tried a 50/50 mix but it didn't seem to retain the nice properties of the Aurora.

What is the minimum amount of the Noodler's needed to have some bulletproof qualities, 1:10, 1:50, or even 1:100? I love Aurora black and like the security of the bulletproof black but I don't like the nib creep, the flow, or thinness of the line the Noodler's produces. Any thoughts?

If you want Noodlers to flow more, try adding some Tryphon ink additive. I doubt you'll get rid of the creep without watering Noodlers a lot.

Okay, diluting an eternal ink with a nonwaterproof ink will leave a faint line to the faintness of a comparable dilution with water. You won't be able to see much at 1:100 (maybe a faint yspectre of the words you'd written). I've found that 1:5 and 1:4 dilutions of an eternal with a conventional washable ink are great to make the ink semibulletproof but largely "invisible" to the superior qualities and shades of the dominant ink (if they're very similar in color)...

Unless you're worried about forgers going after your documents with bleaches and such (which I'm not deriding, that's a definite concern in some situations, and completely invalidates what I'm about to say ), Aurora Black on its own may be sufficiently bullet-resistant. I tested the ink a while back, and found it to be extremely water-resistant. It will fade slightly when soaked long enough, but I couldn't get it to smudge. I could eradicate it by rubbing the wet page, but only because that scraped off the top layers of the paper.

Here's the result of that ink test:

Click to view attachment

So, depending on your requirements, Aurora Black may be good enough on its own, without having to compromise with nib creep.

[acronym="in my experience"]IME[/acronym] an 8:1 mixture of non-waterproof ink to Noodler's Black ink leaves a readable, gray line after the non-waterproof ink has been washed away. I'm sure that a 10:1 ratio would leave almost as much readable Noodler's Black ink as well.

As for the flow, or thinness of the line with Noodler's Black, I don't see that happening with my scribbles. Of course [acronym="Well, obviously yours does vary"]YMMV[/acronym].