I Know that this is not fresco, but I'll ask this here because it's similar! :)

I need to know if dry pigments mixed with distilled water can be spread over watercolour paper to create a medium that will look and behave, when dried, like a pastel (I would like to make this because pure pigments have more chroma than pastels).
Can I fix a painting made like that with regular pastel fixative?
Can I paint with this kind of medium over canvas primed with universal primer (as long as I fix this medium)?
Can I paint with oil colours or acrylics over this dried and fixed medium? Or should I use this medium only over acrylics?
Thanks for your replies!
Nelson

You have an interesting question. Yes, you can do it granted you are applying it thin, water colour like. But then why not to use water colour to begin with.
What makes paint "stick" is the medium pigments are ground/mixed into. With fresco this medium is lime as it dries it crystallizes and "traps" the pigment within. Water is just a vehicle to deliver the pigment.

Technically you can just spread dry pigment on the paper rub it in and spray with fixative (adding water, in relation to pigment's binding chances, will be just an extra step but it will not improve or alter binding itself). If that will work for you, then your system is possible (I do not know how "thick" you want the color to be nor the exact look you are trying to achieve).

hope that helps

and Welcome here

ilia

I just got back from Portugal to USA ( but I am from Hungary)..
In Lisbon at Pap'acorda restaurante R. da Atalaia 57-59
(ao Bairro Alto) tel:21-3464811..they got one wall,a most amazing blue and I saw the same in Sintra ...
my question to you ,would you know what did they use (probably marble dust)...and I don't know what else,
I would like to make the same with my wall...I do not know how to figure it out what to mix and where to get it from :)

I'm just taking my chance if you would know anything about it,thanks in advance !

(your country is very beautiful !)