If you are using this paper can you still blend your colours on it please?
The Clairefontaine Pastelmat paper offers a smooth but grippy surface making it perfect for pastels without the need for a fixative.
The first layers are more difficult to blend as they are gripped to the surface. A little blending can be achieved but this takes some effort. subsequent layers of pastel become much easier to soften and blend.
If you would like to see these in action then you can go here and watch the Jeremy Ford pastel workshops. Jeremy is a great advocate for Pastelmat paper and you can judge how easy it is to blend.
I hope this helps.