What is the difference between fine grout aggregate as defined by ASTM C 404 "Standard Specification for Aggregates for Masonry Grout" and mortar sand meeting the requirements of ASTM C 144 "Standard Specification for Aggregates for Masonry Mortar"?
Fine aggregate as defined by ASTM C 404 can be either masonry sand as defined by ASTM C 144 or concrete sand as defined by ASTM C 33 "Standard Specification for Aggregate for Concrete." Sand for mortar should conform to the grading requirements of ASTM C 144.