what mortar to use?

I had placd a similar post in the fireplace section as that is what this stone is going around in our basement but maybe it is better suited here so that I may get some responses.

We are going to try and put some stone around our fireplace from Elderado or Owins Corning (I would assume the company really doesn't make a difference as long as it is all the same stone type?). We are the stage where we apply the scratch coat. The videos I have watched on owins corning and the elderado stone sites say to use a "Type N" mortar. Is that for the scratch coat too? Also, when I went to Lowes and Menards, nobody had ever heard of a "Type N". What mortar should I use at Lowes or menards for the scratch coat? The brand they sell is Mapei I believe.
Thanks for the help.

 

Go to a real hardware store.Type N mortar is regular brick mortar sometimes called mortar mix.

Can't tell you about the scratch coat though...sorry.