I have and love Hiris by Hermes, so I wanted to try more iris, and based on the reviews (mistake!) I bought this one.
I don't understand how it can be described a gritty, earthy, austere. I guess my nose misses something, and probably I'm not sophisticated enough, but to me it smells artificial, powdery, cloying, perfumey - in short, all I dislike in a perfume.
Compared to it, Hiris shines even more: it's sober, bracing, fresh, elegant, subtle.
To me, Iris Bleu Gris is perfume an old lady of not particularly refined taste could wear.
If you like iris, you'll love it. If you don't, you won't. Floral to a fault and turned rancid on me. It has very good lasting power and has a lot going on, but not something I could wear at all.