Artificial light, two coats:
Posh Bird is a taupey-purple base with dense silver microshimmer. It's definitely in the "mushroom-colors" family, which happens to be one of my favorite families.
I do like this polish, and it would flatter many skin tones- a really easy color to wear. I'm not over the moon about it though. I think it's one of those colors that, aesthetically, you really love examining up close, but when you see your hands in the mirror, it's just like 'eh.' Why is that?!
Maybe it will grow on me- it's a nice color, and I have never seen a taupe like this with shimmer, or at least I can't think of one.
Up close, to get an idea of the finish/ shimmer:
It's your basic super-dense microshimmer finish.
Formula: Really nice, I had no issues. Some people might think it is too thick, but it's not gloopy at all. Covers in two coats, as long as you don't wimp out and make them too thin (like I did on my ring finger- can you see the VNL?! Oops. I didn't notice it until I started taking photos.)
And, I don't have much of anything exactly to compare it to (which makes me happy, because I hate buying dupes!).
Here it is next to Sally Hansen Complete Salon Manicure- Commander In Chic, so you can get an idea of the taupe-i-ness:
Sally Hansen CSM- Commander In Chic, Butter London- Posh Bird
(Please excuse how beat-up my Commander In Chic is! It is a well-loved and oft-traveled polish.)
I do think that Posh Bird's base color is closer to Commander in Chic than it looks here. All that silver shimmer makes the polish look a lot cooler when the light hits it.
Butter London- Posh Bird, Nubar- Gem, Sally Hansen CSM- Commander In Chic
And although Nubar- Gem is holographic and much more in-your-face-sparkle, they have a similar tone going on. Again, Posh Bird's dense microshimmer makes it look really silver in comparison (at least in the lightbox).
And, lastly, here is Posh Bird next to Butter London- All Hail The Queen, which I think might help resolve some issues for people. They aren't really close at all:
Butter London- All Hail The Queen, Butter London- Posh Bird