Some of these issues have been adressed but here it is all in one place:

We're installing a square/rectangular cut, random size Brazilian bluestone porch/entry about 250 sq, ft. over an already poured reinforced concrete slab that sits about 3 ft above ground level - all exposed to the elements in CT. Should we go with a thermaled bluestone; 1 in or 1 1/2 in.? What is the best mortar mix to use for this? What is the best jointing or grouting mix (1/4" joints)? for this? (Should I consider adding any latex additive to either mortar or grout mix? What about thinset to set the stone in)? Should I create control joints - where, how many feet and how is this best done? What more do I need to know? Thanks in advance.