Mortar is a mixture of Portland cement and sand and is also useful for bedding masonry units such as concrete block, brick, and stone. Common mortar also incorporates lime, which makes the mortar stickier, so it stays over the ends of every brick or block as it’s staying positioned. Mortars https://www.whofish.org/Default.aspx?tabid=45&modid=379&action=detail&itemid=284671&rCode=33