Synthesis of americium dioxide, as described by the Oak Ridge National Laboratory in 1960, starts by dissolving americium in hydrochloric acid, and then neutralizing the excess acid with ammonium hydroxide (NH 4OH). Then, saturated oxalic acid solution (C 2H 2O 4) is added to the now neutralized solution to precipitate dull pink americium(III) oxalate crystals; once complete precipitation is achieved, additional oxalic acid is added to make a slurry. The slurry of americium oxalate and oxalic acid is next agitated before the americium oxalate is filtered out, washed with water, and partially dried in air.[1]