In the inner corner behind my stove are two minerit boards that I have plastered (though I can't remember if I used B or KC). It seems to work perfectly fine. I limed the plaster afterward, which is guaranteed to withstand heat. The only downside is that it may chalk a bit if you rub against the wall.
I get to build one of these, so I don't need to stand and rub my back against the plaster wall. 
Now it's done.
I bought Beckers silicate paint and their medium-coarse texture agent, a white dolomite sand.
First, I primed the minerite once with some diluted silicate paint.
Then I applied the silicate paint mixed with sand, using one of those small roller sets for 10:- from Biltema, thinking it would definitely be single-use.
And YES, the sand cannot be washed out completely in any way.
Then I carefully removed the most loosely attached sand and trimmed down a few overly high peaks.
And finally, a finish coat with just the paint, so the sand adheres better and everything definitely gets an even white appearance.
It looks good, but I didn't get any brush streaks in the "plaster," maybe I could have if I fiddled with it more, but it was easy to brush away all the sand when I tried to apply a bit of pressure, and it didn't look particularly good, basically a smooth white-painted minerite surface surrounded by white plaster type.
So I left it.
I forgot to take a picture, and it wasn't fully dry when I left yesterday, but I can take a photo later.
I bought Beckers silicate paint and their medium-coarse texture agent, a white dolomite sand.
First, I primed the minerite once with some diluted silicate paint.
Then I applied the silicate paint mixed with sand, using one of those small roller sets for 10:- from Biltema, thinking it would definitely be single-use.
And YES, the sand cannot be washed out completely in any way.
Then I carefully removed the most loosely attached sand and trimmed down a few overly high peaks.
And finally, a finish coat with just the paint, so the sand adheres better and everything definitely gets an even white appearance.
It looks good, but I didn't get any brush streaks in the "plaster," maybe I could have if I fiddled with it more, but it was easy to brush away all the sand when I tried to apply a bit of pressure, and it didn't look particularly good, basically a smooth white-painted minerite surface surrounded by white plaster type.
So I left it.
I forgot to take a picture, and it wasn't fully dry when I left yesterday, but I can take a photo later.
Yes, it's really not easy to photograph a white-painted wall with plaster texture, especially with a regular but low-quality compact camera and without any special lighting to work with. :x
But here's a teaser.
I will post a picture of the entire setup later when the stove is in place, in this thread:
http://www.byggahus.se/forum/biobraensle/172249-posta-bilder-pa-er-kamin.html
But here's a teaser.
I will post a picture of the entire setup later when the stove is in place, in this thread:
http://www.byggahus.se/forum/biobraensle/172249-posta-bilder-pa-er-kamin.html
Do I understand correctly that you placed the granite on a minerit board? How did you attach it? I have minerit (glued on chipboard) in the hall and was thinking of laying tiles on it, but I've been told that you can't place tiles or ceramics on minerit because it comes off.