... since 1986 *Features Boric acid, also called hydrogen borate, boracic acid, orthoboric acid and acidum boricum, is a weak acid of boron often used ... as a mineral, it is called sassolite. ItemIndexFirst gradeSecond gradeBoric acid(%)≥99.5%≥96.5%Water insolubles(%)≤0.05%≤0.15 ... )(%)≤0.003%≤0.005% The primary industrial use of boric acid is in the manufacture of monofilament fiberglass usually referred to ...