*Mortar (masonry cement and sand mix) should be the best quality available and is available in 40 and 80 lb bags at home improvement stores. For larger projects it is more economical to mix Mortar cement, type S, with masonry sand (1 part cement to 2-3 parts of sand depending on how fine the sand is.
Epoxy or construction adhesive like that used for concrete blocks can be used to set small rock pieces, eliminating mortar mess. RicoRock® Waterproofing also works as a thin set, eliminating the mortar joint.
