Henley Regatta, Thames, and the blue/green issue

This is Butter London Henley Regatta and Thames:

Henley Regatta was the first Butter London polish I ever bought. It's a bright blue-green, heavily packed glitter. I really love it, but it has that problem where it sometimes flakes off in big pieces - which I later learned is apparently an issue with many of BL's glitters. I bought Thames later, and it was described as an emerald green - but it looks to me like exactly the same color as Henley Regatta, except instead of being a glitter it's a heavy shimmer. Questions like this happen at every transition on the color wheel, but for some reason it seems to me that the blue-to-green transition is one where people really have big disagreements about which is which. (I'll have some more examples of this coming up.) I don't actually mind that Thames isn't emerald, understand; I think it's a really pretty color. But it's not emerald.

"Teal" is also problematic. I've already shown you a couple of polishes with "teal" in their names (Teal Of Fortune, Teal The Cows Come Home) but both of those read pretty much blue, to my mind. I would actually call both the polishes above teal - and I guess I would the one below, as well (which is unlabeled):

The color as it appears in the bottle and the color you end up with on the nail are pretty much entirely different, here.

(Then there's turquoise, which can be blue-green - the actual turquoise stones sometimes lean very green - but a lot of the time is used to mean plain old bright cyan blue. Talking about color is just a very chancy thing, let's face it.)