I may be coming into this one with a bias, since teal is my favorite color and the northern lights are one of the most amazing things I've ever seen, but this is just gorgeous. Even with an extremely fine nib, there's clear shading between lighter and darker teal, and a subtle hint of blackish red comes out around the edges of the darker lines. I love this extremely much. Additionally, it doesn't bleed through at all on Leuchtturm 1917 paper, and it seemed to dry pretty quickly (though the sheen around the edges took longer to appear). I am new enough to fountain pens and ink that I don't feel like I can accurately evaluate flow/shading/etc., but hopefully the photo will be helpful to more experienced people. I'm already quite sure I'll be buying a full bottle of this.

Very glad I got the sample! The shading is very nice, it flows good from my flex pen. Im getting the full sized bottle

This is a dark, almost black looking cooler teal in a fine nib. It was too much like Noodler's Grinch and other similar inks that could be used in a business setting because it looks so much like black.

I found Diamine Velvet Emerald (purple edition) to be a richer, warmer shading ink with a slight red sheen that doesn't dry up in the feed and cleans out of the pen easily and completely. Unlike Diamine Holly, it dries quickly and doesn't smear weeks after writing with it.

This is a lush, vibrant, medium-deep green-leaning teal along the lines of Colorverse Gravity Wave and Sailor Shikiori Yamadori but not quite as deep as those two nor as red-sheening. It shows a little bit of purple sheening where the ink pools heavily but is mostly well-behaved although slightly dry off of a glass pen. It probably shades nicely from a fountain pen.

Aurora Borealis is a gorgeous color! We’ve tried the sample with a glass dip pen and I’ll be purchasing a bottle in my next order from Goulet Pens.

This ink is a wonderful dark teal. It writes wet, but is very gentle on worse papers. It's a good match for the color of my TWSBI 580ALR in the Prussian Blue.

Diamine Aroura Borealis is one of my favorite inks. It writes very well and smooth out of my TWSBI ECO.

I love using this ink, anybody looking for a nice everyday ink to use anywhere should give this a try, I am very picky with my inks and I love love this ink!!

The ink flows well and is a beautiful color. I will definitely buy the full size bottle.

Gorgeous color!

Lovely color and dries surprisingly quickly (very important since I'm left-handed).

In a Lamy Safari EF nib, the ink color was definitely on the darker end of the spectrum and can work in a professional setting. It does not look like the picture sample on the webpage. It's a very saturated color and performs very well. Dry time is also adequate and does not feather on cheap notebook paper. It does very very slightly bleed through the back if you write over the ink more than once.

I love this ink! I got a sample for my TWSBI eco EF. I am a college student, and this ink has made note taking so much more enjoyable! (Especially with all my classes getting moved online) The ink is working well on my standard 5star notebooks. Such a lovely color! I would classify it as teal because I think it is a little more green than blue. I love it!

Very pretty color, quite similar to Monteverde California Teal, which is one of my favorites. Aurora Borealis is more blue-toned, and I didn't see any sheen on it - not clear if there's supposed to be any with this one. Overall, I prefer the California Teal, but if you like a more blue-leaning teal, this one might be for you.

In my opinion this is a nice green-teal color that hints at turquoise when used lightly. Tried this using a glass pen. Very smooth and dries quickly. I prefer to lay this ink down rather thick - that's when the depth of color really shows with a hint of red at the edges. I didn't see any shading, but that may have to do with the glass pen. If you like green, this is a nice choice.

I'm loving this gorgeous color. It was so fun to be able to participate in the Reddit process and make it!