Today I discovered &OtherStories beauty department. More of which in due course. I bought one nail varnish to check quality etc before going mad.
The colour is called Vintage Denim. I can never resist blue. This one is a perfect dusty blue for Spring. I like it a lot. Quality-wise, of course you know you're not using YSL grade polish but it's ok once the second coat goes on. The brush is easy to work with. They don't appear to be on their site anywhere which is odd so I think you're out of luck unless you are in London as I don't think they have shops anywhere else in the UK.