How to Pick The Right Mortar
Unless you're a professional mason, it's wise to heed the manufacturer's suggestions. In general, type N mortar and the stickier type S give you the flexibility to place and adjust the veneer, but various additives can influence the set time, the water resistance, and the bond strength between the mortar, the stone, and the substrate. While considering the choices, inquire about color options, too. Many suppliers offer pigments that help you shade the mix to match the stone.