This is one of those polishes that does what it says on the bottle, Revlon Blue Slate which is a slate blue creme!
It's from the new-ish Revlon Colorstay range available in the UK from Boots. I picked up a handful of these (3 for 2) about 6 months ago and so far I've been impressed with the polish, if not the brush.
Unfortunately (for me as I know lots of others love them) these come with a wide flat brush. It's not super huge but still a little unwieldy for my tiny nails. Thankfully the formula more than makes up for it - this is a highly pigmented one-coat wonder. This is also one of those polish formula that has almost an enamel type finish.
The bottles are also different from the classic triangle shaped Revlon bottles, makes them look more modern to me.
I didn't test the 'Colorstay' of these polishes though - anyone else have any comments as to their longevity?