“…The reagent which has found widest use is aluminon", ammonium aurintricarboxylate (4, 8, 15). In spite of interference by chromium, iron, beryllium, vanadium, titanium, and gallium, it has been used for colorimetrically determining from 0.04 to 1.5% of aluminum in steel (2), and for low percentages in nonferrous alloys (10). Ether extraction and mercury cathode electrolysis were used, respectively, as separations in these two procedures.…”