I see one problem right off the bat.....you have 'world orientation'  checked instead of 'object orientation'.   The difference is that any other object with the same material (perhaps a larger mountain in the background) will affect the material on the first object in 'world orientation'. If using the object orientation, then each object keeps it's material integrity.  Took me quite a few headaches before I figured that one out........my snow on the forground kept disappearing when I tried to put the same mat on background mountains. 

And I would also go with three mixed materials instead of  snow and a two tone mat.....(or maybe you did, I can't tell from here)...mix the rock and snow with environment settings and save it. Then make your bottom mat and mix it with the one you just saved again with environmental settings. That should let you adjust all three layers separately. Make sure all mats are set to object standard or parametric...not world or the same as the above will happen.

Here's an example...hope it helps....