“Heat Stop® Refractory Mortar was developed by Robert A. Rucker in the mid-1970’s. Mr. Rucker found that mortars used for fireplace and chimney construction were not high-temperature resistant, were not acid resistant, or were water soluble. Armed with technology from the U.S. industrial refractories industry and determined to succeed, he developed a formulation with the appropriate characteristics that addressed these problems. U.S. and Canadian patents were awarded. Over the years, several additional mortar products were developed and existing products were improved. Today, Heat Stop Refractory Mortar is the industry standard throughout North America for mortar used in high temperature resistant masonry construction."