This high-grade, coarse anhydrous borax flux keeps your metals cleaner during melts and pours. It is also great for seasoning your graphite crucibles, and while melting, casting, and refining metals such as gold, silver, copper, iron, sterling silver, tin, nickel, and their alloys. Add borax to your melts to draw gasses and oxides out of molten metal. Made in the U.S.A.