Mortar is a mixture of Portland cement and sand and it is used for bedding masonry models like concrete block, brick, and stone. Traditional mortar also incorporates lime, which makes the mortar stickier, so it stays on the ends of each and every brick or block because it’s remaining positioned. https://www.whofish.org/Default.aspx?tabid=45&modid=379&action=detail&itemid=284671&rCode=33