Playing around with some of my more interesting inks, I thought I'd catalog the blue-green shades and see where they fit on the spectrum.
The greenest of the blue-greens is Noodler's Squeteague. In swabs it may look more blue, but this is actually a deep pine green with an undertone of blue.
Next is Iroshizuku's Syo-Ro, which is describes as a dark turquoise. It's blue with just a hint of green to it, and I have to say I was impressed by the color and wondering why I don't use it more.
The two that are most similar are De Atramentis Sherlock Holmes and Diamine Twilight, dark night sky blues with a touch of green to deepen the hue.
Finally, there is Diamine Teal. Teal looks as if it is more a 50-50 blend of blue-green than any of the others and perhaps the standard for that mix of color.