My main application for Oxalic would be for the bleaching of teak (or any wood for that matter)decks on boats. You can dissolve 1/3 - 1/2 cup of crystals in a gallon of water. Apply with bristle brush, scrub lightly. Let soak into wood until desired tone is achieved (usually 10 - 15 minutes is plenty). Rinse thoroughly to neutralize acid. May also broadcast crystals over wet surface, scrub lightly and rinse. Another application would be for the removal of rust....dissolve 2 - 3 tablespoons of crystals in a gallon of water. then let metal objects (brackets, nuts, bolts, etc.) for 20 30 minutes or so. You will be amazed! Will not harm chrome, glass or painted surfaces. Great for removing rust from motorcycle tanks as well!